Procedure for production of metal item containing another component-additive without melting
SUBSTANCE: invention refers to production of item out of alloy alloyed with alloying agent without melting. There is prepared a mixture of a non-metallic compound-precursor of basic metal and a non-metallic compound-precursor of an alloying element. Compounds-precursors are chemically reduced to metal alloy without melting. There is introduced one or more component-additive and metal alloy is compacted producing a packed metal item without melting. Also the component-additive is introduced during preparation of mixture or during chemical reduction, or upon chemical reduction. Additionally, an element, mixture of elements or a chemical compound are used as the component-additive. Notably, the component-additive is dissolved in a matrix or creates discrete phases in micro-structure of the alloy and is not reduced at the stage of chemical reduction.
EFFECT: facilitating production of items out of homogeneous alloy without melting its constituents causing oxidation; also composition of this alloy is impossible to produce by any other procedure.
9 cl, 3 dwg
This application is an application form in a partial continuation of patent application U.S. serial No. 10/172,217, filed on June 14, 2002, for which priority is claimed and the contents of which are incorporated here by this reference; and in the partial continuation of patent application U.S. serial No. 10/172,218, filed on June 14, 2002, for which priority is claimed and the contents of which are incorporated here by this reference; and in the partial continuation of patent application U.S. serial No. 10/329,143, filed December 23, 2002, for which priority is claimed and the contents of which are incorporated here by this reference; and in the partial continuation of patent application U.S. serial No. 10/350,968, filed January 22, 2003, for which priority is claimed and the contents of which are incorporated here by this reference; and in the partial continuation of patent application U.S. serial No. 10/371,743, filed February 19, 2003, on which priority is claimed and the contents of which are incorporated here by this reference.
The scope of the invention
The present invention relates to the production of products made of metal alloy containing another component-additive, without melting the metallic alloy.
The level of technology
Products from metal alloys produced using any of many known technologies, sootvetstvujushij the nature of the product. According to one well-known technologies of metal-containing ore is cleaned from impurities (rafinuyut) receiving molten metal, which is then bottled. Metal ores are cleaned as necessary to remove or reduce the content of undesirable impurity elements. The composition of the pure metal can also be modified by adding the desired alloying elements. These stages of purification and alloying can be performed during the initial process of smelting or after solidification and re-melting. After receiving the metal of a given composition can be used in the cast condition, i.e. in the form in which it was cast, in the case of certain alloys of compositions (i.e. casting alloys) or may be subjected to mechanical processing to give the metal the desired shape in the case of alloys of other compositions (i.e. deformable alloys). In any case, can be used for additional processing, such as, for example, heat treatment, machining, coating on surface etc.
As different applications have the metal products increasingly stringent requirements, and expansion of knowledge in the field of metallurgy, related to the interdependencies between composition, structure, processing technology and has achieved is the subject characteristics, in the main manufacturing process was made a lot of changes. However, as each limit on achievable performance were overcome through improvements in processing technology, has introduced new restrictions pumping characteristics that had to be overcome. In some cases, limitations on achievable performance can be easily overcome, however, in other cases, the possibility of overcoming such limitations hinder the fundamental laws of physics related to the technological processes of manufacturing and private properties of metals. Each potential change processing technology and the resulting improved performance is evaluated from the point of view of the cost of such changes in processing technology in order to determine whether it is economically acceptable.
In many areas it is still possible the gradual improvement of the characteristics resulting from changes in processing technology. However, in the course of the work leading to the present invention, the authors found that in other cases, the main production technology imposes fundamental limitations on achievable performance, which cannot be overcome at any reasonable cost. They identified the need to move away from the normal of the times thinking, related to manufacturing techniques that will allow you to overcome these fundamental limitations. The present invention satisfies this need and provides appropriate benefits.
Disclosure of invention
In the present invention proposes a method of obtaining products, made of metal alloy, such as titanium, aluminum, iron, Nickel, cobalt, ferro-Nickel, an alloy of iron-Nickel-cobalt and magnesium. The proposed technology allows you to bypass those problems that cannot be avoided during the smelting or which can be bypassed only with great difficulty and at great cost. The proposed technology allows to obtain a homogeneous alloy, without exposing its components influence the conditions that lead to problems, in particular the melting process. This avoids unintentional oxidation of the reactive metal and the alloying elements. The proposed technology allows to obtain products with such compounds, which cannot easily be obtained in other ways in commercial quantities, including products containing other components of the additive and, optionally, contains thermophysical incompatible with alloying alloying elements.
The proposed method of producing articles of base metal doped alloying element, including the em in the stage of preparation of compounds of the predecessor by phase ensure the availability of chemically recovered non-metallic compounds-the predecessor of the base metal. The method further includes the step of chemical recovery mentioned compounds, precursor of the metal alloy, without melting the metallic alloy. The stage of preparation or stage chemical recovery includes the step of adding another component-additive. After that, a metal alloy seal (integrate) with the receipt of sealed metal products, without melting the metallic alloy and without melting the consolidated metallic article. Stage cooking can, optionally, include additional steps to ensure the availability of chemically recovered non-metallic compounds-the predecessor of the alloying element, and then mixing the above compounds, a predecessor of the base metal and the above-mentioned compounds, a predecessor of the alloying element with the formation of a mixture of compounds. May be also an additional step response of another component-additive.
Non-metallic compound precursor may be a solid, liquid or gaseous. Chemical reduction is preferably carried out by solid-phase recovery, such as electrolysis in molten salt compounds, the precursors, in fine particulate form, e.g. the measures in the form of oxide of the element, or by vapor recovery, for example, by contacting in the vapor phase of the halides of the base metal and alloying (-) item(s) with liquid alkali metal or liquid alkaline earth metal. The finished product preferably contains more titanium than any other element. However, the proposed technology is not limited to alloys based on titanium. Issues currently of interest alloys include alloys of aluminum, alloys of iron, alloys of Nickel, alloys ferro-Nickel (iron-Nickel), alloys of cobalt, alloys based on iron-Nickel-cobalt, and alloys based on magnesium, however, this technology is applicable to any alloys that have a non-metallic compound precursor, which can be restored to the metallic state.
The term "another component-additive" is defined in the present invention as an element, a mixture of elements or (chemical) compound, (who or which) is part of the content of the final alloy and is entered through a process that is different from the recovery process used for the formation of the base metal. Another component, the additive can be dissolved in the matrix, or may form a discrete phase in mi is restructure. Another component, the additive may be imposed under any feasible technology, with particular interest are the four technologies. According to the first technology, the stage of preparing includes the step of introducing another component of the additive in the form of an element or compound and mixing the other component is additive to the above-mentioned compounds predecessors, these compounds, the precursors are recreated on stage chemical recovery, and the element or the compound containing (-) another component is additive, not restored on stage chemical recovery. According to the second technology stage chemical recovery includes the step of mixing the solid particles containing the other component is additive, with the said metal alloy. According to the third technology stage chemical recovery includes the step of deposition of another component of the additive from the gas phase to the surface of the metal element or alloy or on the surface of the connection predecessor. According to the fourth technology stage chemical recovery includes the step of deposition of another component of the additive from the liquid phase to the surface of the metal element or alloy or on the surface of the connection predecessor. The metal may be entered in more than one other whom onent-additive. One or more of the above-mentioned technologies the introduction of other components and additives may be used in combination. In some examples, the first technology can in practice be used once for the introduction of one or more than one other component of the additive; or the first technology can in practice be used more than once for the introduction of more than one other component of the additive; or the first technology can in practice be used to introduce one or more than one other component of the additive, and the second technology can in practice be used to introduce one or more than one other component of the additive.
The proposed technology is the introduction of another component of the additive is compatible with the addition of alloying elements, thermophysical incompatible with the fusion. The alloys may contain one or more elements, thermophysical incompatible with the fusion, and one or more elements that are not thermophysical incompatible with alloying with the base metal.
Thus, in another variant embodiment of the proposed method for products made of base metal (such as described above), doped alloying element, includes the preparation of a mixture of compounds through the implementation stages ensure cash is being chemically recovered non-metallic compounds-the predecessor of base metal, ensure the availability of chemically recovered non-metallic compounds-the predecessor of the alloying element (which is optional, is a thermophysical incompatible with alloying with the base metal) and the subsequent mixing of the compounds of the precursor base metal and connecting the predecessor of the alloying element with the formation of a mixture of compounds. The method further includes chemical reduction mentioned mixtures of compounds with production of metal alloy, without melting the metallic alloy. The stage of preparation or stage chemical recovery includes the step of introducing another component of the additive. Metal alloy then condense (integrate) with the receipt of sealed metal products, without melting the metallic alloy and without melting the consolidated metallic article. In this variant embodiment can be used, and others described herein and compatible signs.
In the proposed method may be included with some additional processing steps. In some cases, it is preferable that a mixture of compounds, the precursors was pressed after the stage of mixing and before the step of chemical recovery. The result is a compacted mass, which, Bud the Chi chemically restored, gives a spongy metallic material. After stage chemical recovery metal alloy is compacted with getting compacted metal products, without melting the metallic alloy and without melting the consolidated metallic article. Such a seal may be effected in any physical form of a metallic alloy obtained by a chemical recovery, but this technology has particular advantages when applied to the seal pre-compressed sponge. The seal preferably is performed by hot pressing, hot isostatic pressing or extrusion (extrusion), but in any case without melting. To achieve the seal can also be used diffusion of alloying elements in the solid state (solid-state diffusion).
Sealed metal product can be used in a compressed state, i.e. the state directly after compaction. In appropriate circumstances it may also be given other forms using known forming methods, such as rolling, forging, extrusion, etc. This product can also be further processed using known methods, such as mechanical dimensional machining, heat treatment, coating on the surface is the ability etc.
The proposed technology is used for obtaining the products of the compounds, the precursors, and completely without any melting. As a result, this allows you to avoid the manifestation of the properties of any of the alloying elements, which cause problems during melting, and therefore they cannot lead to inhomogeneity or disorder in the finished metal alloy. The technology, therefore, allows to obtain the desired composition of the alloy with good quality, but without the negative effects associated with the melting of the problems that otherwise would hinder the formation of an acceptable alloy and microstructure.
The proposed technology is different from previous technologies that large-scale metal does not melt. Melting and related processing, such as casting, are expensive and lead to certain undesirable microstructures that are either inevitable, or can only be changed with additional costly modifications of the process. The technology reduces costs and avoids receiving structures and neuporyadochennosti associated with the melting and casting, with the improvement of the mechanical properties of fabricated metal products. This technology, in some cases, the result is an improved ability to more easily manufacture of products of special forms and types and to facilitate the control of such products. Additional advantages are realized in relation to specific systems, metal alloys, for example, is provided by the reduced formation of alpha-shell" (from the English. "alpha case"), i.e. brittle surface layer exclusively of alpha-phase, susceptible to this phenomenon of two-phase titanium alloys.
Preferred option the proposed technology also has the advantage that it is based on the powdered precursor. When the processing starts with non-metallic compounds, the precursors, it avoids the cast structure with related inhomogeneities,such as segregation of elements (porosity) on non-equilibrium microscopic and macroscopic levels, cast microstructure with a range of sizes and morphology grains, which have somehow homogenize for many applications, capture gases and pollution. The proposed technology provides a uniform, fine-grained, homogeneous, not having been without gas since and lightly polluted final product.
Other characteristics and advantages of the present invention will be apparent from the following more detailed description of the preferred variant of embodiment, given with reference to the accompanying drawings, illustrating, as non-limiting examples, the and, the principles of the present invention. Scope of the present invention, however, is not limited to these preferred embodiments.
Brief description of drawings
Figure 1 is a perspective view of a metal product, obtained according to the proposed technology.
Figure 2 is a block diagram of the technological process in the practical implementation of the present invention.
Figure 3 is a perspective view of the spongy mass of the initial metallic material.
Detailed description of the invention
The proposed technology can be used for the manufacture of a wide range of metal products 20, such as, for example, the blade 22 of the compressor of the gas turbine engine shown in figure 1. The blade 22 of the compressor includes aerodynamic profile (pen) 24, the bracket 26, which serves to attach the design to drive the compressor (not shown), and a plane or platform 28 that is located between the aerodynamic profile 24 and the bracket 26. The blade 22 of the compressor is just one example of the types of articles 20, which may be made according to the proposed technology. Some other examples include other parts of the gas turbine, such as, for example, fan blades, disks, fans, drives the compressor, shovels and turbine, drives the turbine, bearings, one piece design, consisting of made integral disk and blades (from the English. "blisks"), housings and shafts, parts of automobiles, biomedical products, as well as elements of design, such as design items (fuselage) of the aircraft. There are no known restrictions on the types of products that can be manufactured according to the proposed technology.
Figure 2 shows the preferred technology of manufacturing of articles of the base metal and the alloying element. The method includes ensuring the availability of chemically recovered non-metallic compounds-the predecessor of the base metal, the stage 40, and the availability of chemically recovered non-metallic compounds-the predecessor of the alloying element, the stage 42. "Non-metallic compound precursor" represent the non-metallic compounds of those metals, which eventually form the metal article 20. Can be used with any suitable non-metallic compound precursor. For solid-phase restoration of the preferred non-metallic compounds-predecessors are recoverable metal oxides, however, can be suitable, and other types of non-metallic compounds, such as sulfides, carbides, halides and NITR the water. Recovered metal halide is the preferred non-metallic compounds-predecessors when restoring in the vapor phase. The base metal is a metal that is present in larger quantities (in mass percent)than any other element in the alloy. The connection of the base metal is present in such quantity that after chemical recovery, which will be described below, the metal alloy was attended by more base metal than any other element. In the preferred case, the base metal is titanium, and the connection of the base metal is titanium oxide, TiO2(for solid-phase recovery) or titanium tetrachloride, TiCl4(vapor recovery). The alloying element may be any element present in chemically recovered combination of the predecessor. A few illustrative examples include cadmium, zinc, silver, iron, cobalt, chromium, bismuth, copper, tungsten, tantalum, molybdenum, aluminum, niobium, Nickel, magnesium, manganese, lithium, beryllium and rare earth elements.
Non-metallic compound precursor is chosen in such a way as to ensure the introduction of the necessary metals fabricated metal products, and mix them together in the correct proportions to obtain n the necessary share of these metals in the metal product. These compounds are precursors taken and mixed in the correct proportions so that the ratio of the base metal and alloying additives in the mixture of compounds, the precursors was so needed in the metal alloy forming the finished product.
The connection of the base metal and alloying connection are fine solid particles or are in the gaseous state to guarantee their chemical reaction at a later stage. Fine connection of the base metal and alloying connection can represent, for example, powders, granules, flakes or the like, the Preferred maximum size in such fine form is about 100 micrometers, although it is preferred that the maximum size was less than about 10 micrometers to ensure good reactivity.
The proposed technology can be used in combination with alloys, thermophysical incompatible with the fusion. The term "thermo-physical incompatibility with fusion" and related terms refer to the basic concept is that any identified thermophysical property of the alloying element is quite different from the same properties of the base metal, in the preferred case is Ethan, in order to cause harmful effects in fused the finished product. These harmful effects include such phenomena as chemical inhomogeneity (harmful microsegregation, macrosegregation, such as, for example, spot the beta phase, and full segregation caused by evaporation or immiscibility), inclusion of alloying elements (for example, enable a high density of elements such as tungsten, tantalum, molybdenum and niobium) and other Thermophysical properties inherent in the elements and combinations of elements, which form alloys, and usually they are using the equilibrium phase diagrams, the curves of dependence of vapor pressure on temperature curves of density on the crystal structure and temperature and other such approaches.
Although the system alloys can only be close to the predicted equilibrium, these represented on the chart gives information sufficient to recognize and predict thermophysical incompatibility with fusion as the reasons mentioned harmful effects. However, the ability to recognize and predict these adverse effects as a result of thermo-physical incompatibility with the fusion does not eliminate these effects. The proposed technology provides a way to minimize such adverse effects, it is advisable to avoid them the way the exception of melting upon receipt and processing of the alloy.
Thus, thermophysical incompatible(s) with alloying alloying(s) the item or items in the resulting alloy does not give a stable and controlled manner well-mixed, homogeneous alloy with the base metal during the operation of its receipt by melting. In some cases, thermophysical incompatible with alloying alloying element can easily be introduced into the alloy of any composition level, and in other cases, this alloying element can only be entered at low levels but not at high levels. For example, iron is not behaving thermophysical incompatible with the fusion in the case, when it is introduced into the titanium at low levels, typically up to 0.3 weight percent (wt.%), that allows to obtain a homogeneous titanium-iron-containing alloys with low content of iron. However, if iron is introduced into the titanium at higher levels, it shows a strong tendency to segregation in the melt and, thus, behaves thermophysical incompatible with the fusion, and therefore homogeneous alloys can be obtained only with great difficulty. As other examples when melted in vacuum titanium injected magnesium, the latter immediately starts to evaporate due to low pressure of its saturated is about couple, and therefore heat cannot be conducted in a stable manner. Tungsten has a tendency to segregation in the melt titanium because of its difference with titanium in density, which makes obtaining a homogeneous titanium-tungsten alloy exceptionally difficult task.
Thermophysical incompatibility of the alloying element with alloying with the base metal can refer to any of several types. Since titanium is the preferred base metal, in the following description of several illustrative examples for titanium.
One type of such thermophysical incompatibility with fusion is the saturated vapor pressure, i.e. the case when the alloying element is the evaporation rate, more than about 100 times greater rate of evaporation of titanium in the melt temperature, which is preferably slightly above the liquidus temperature of the alloy, i.e. the junction temperature of this alloy in the liquid state. Examples of such alloying elements in titanium include cadmium, zinc, bismuth, magnesium and silver. When the vapor pressure of the alloying element is too high, mainly evaporates it, as indicated by the value of the evaporation rate with joint fusion with titanium in vacuum in the usual practice of melting. The alloy is formed, however, it is the unstable during melting and continuously loses alloying element, so the percentage of the alloying element in the final alloy is difficult to control. According to the proposed technology, because the operations of melting in vacuum is not carried out, the high vapor pressure of the alloying element during melting is not a concern.
Another type of similar thermo-physical incompatibility with fusion occurs when the melting point of the alloying element is too high or too low compared to the melting temperature of the base metal, i.e. in the case where the melting point of the alloying element is different (either lower or higher) from the melting temperature of the parent metal by more than approximately 400°C (720°F). Examples of such alloying elements in titanium include tungsten, tantalum, molybdenum, magnesium and tin. If the melting point of the alloying element is too high, it is very difficult to melt and homogenize the alloying element in the melt titanium the normal practice of melting in vacuum. Segregation of such alloying elements can result in the formation of high density inclusions containing this element, for example, inclusions of tungsten, tantalum or molybdenum. If the melting point of the alloying element is too low, it is likely to have excessively high pressure nassen the th steam at a temperature required to melt titanium. According to the proposed technology, as melting in a vacuum there, an excessively high or low melting temperatures are not a concern.
Another such thermophysical incompatibility with fusion occurs when the density of the alloying element is so different from the density of the base metal that the alloying element are physically separated in the melt, i.e. in the case where the alloying element has a density difference with the base metal, greater than about 0.5 grams per cubic centimeter (g/cm3). Examples of such alloying elements in titanium include tungsten, tantalum, molybdenum, niobium and aluminum. The normal practice of melting excessively high or low density leads to gravitational segregation of the alloying element. According to the proposed technology, because the melting is absent, gravity segregation can not be.
Another such thermophysical incompatibility with fusion occurs when the alloying element is chemically reacts with the base metal in the liquid phase. Examples of such alloying elements in titanium include oxygen, nitrogen, silicon, boron and beryllium. In the usual practice of melting ability of the alloying element to a chemical reaction with a basic metal which leads to the formation of the molten intermetallic compounds, containing the base metal and the alloying element, and/or other harmful phases, which are retained after solidification of the melt. These phases often have a deleterious effect on the properties of the finished alloy. According to the proposed technology, because the metal is not heated to the temperature at which these reactions occur, such compounds are not formed.
Another such thermophysical incompatibility with fusion occurs when the alloying element has a region of necesitamos with the base metal (limit of solubility in the base metal) in the liquid phase. Examples of such alloying elements in titanium include rare earth elements such as cerium, gadolinium, lanthanum and neodymium. In the usual practice of melting the existence of the limit of solubility leads to segregation of melt compositions determined in this limit of solubility. The result is the field inhomogeneity in the melt, which are stored in the finished cured product. The field inhomogeneity leads to deviations of the properties around the finished product. According to the proposed technology, since the elements do not melt, the question of the limit of solubility does not occur.
Another, more complex type of thermophysical incompatibility with fusion is associated with a strongly stabilizing beta-phase elements (beta-hundred what listorama), demonstrating large "gaps" between the liquidus and solidus in the alloying of titanium. Some of these elements, such as iron, cobalt and chromium, typically exhibit eutectic (or close to eutectic) phase interaction with titanium, and usually undergo solid-phase eutectoid decomposition of the beta phase to alpha phase plus connection. Other elements, such as bismuth and copper, typically show protectionsee phase interaction with titanium, giving the beta phase from the liquid, and likewise usually undergo solid-phase eutectoid decomposition of the beta phase to alpha phase plus connection. These elements create an extraordinary difficult to achieve homogeneity of the alloy during solidification from the melt. This occurs not only because of the normal distribution in the crystallization, causing microsegregation, but also because, as you know, perturbations of the melting process to cause the separation of the enriched beta stabilizers of the liquid during solidification, resulting in areas of macrosegregation, commonly called spotted the beta phase.
Another type of thermophysical incompatibility with fusion is not directly linked to the nature of the base metal, and, instead, is associated with crucibles or the environment in which melts the base metal. The basis of the major metals may require the use of specific material or atmosphere melting, and some potential alloying elements can react with the materials of the crucible or components of the atmosphere melting substances, and, therefore, they are not candidates for consideration as alloying elements for this particular base metal.
Another type of thermophysical incompatibility with fusion refers to such elements as alkali metals and alkaline earth metals, which have very limited solubility in the alloy with the base metal. Examples for titanium are lithium and calcium. Fine inclusions of these elements, for example, beta-calcium alpha-titanium, cannot be easily achieved by using a melting process.
These and other types of thermo-physical incompatibility with the fusion result in difficulty or inability education acceptable alloys with these elements in normal industrial smelting. In the proposed "besplamennoju" technology these harmful effects are eliminated.
The connection of the base metal and the alloying compound is mixed with the formation of a uniform, homogeneous mixture of compounds on the stage 44. Mixing is carried out by conventional means used for mixing the powder in other applications, for solid-phase recovery, or by mixing vapor - to restore the Oia in the vapor phase.
Not necessarily, in the case of solid-phase recovery powders of solid compounds, the precursors, a mixture of compounds is pressed with obtaining preforms (i.e. preformed blanks) at step 46. This pressing is carried out cold or hot pressing of fine connections, but not at so high a temperature at which there is any melting compounds. Such pressing may be subjected to sintering in the solid state for the temporary binding of the particles with each other. Pressing the desired manner yields a shape similar to the shape of the finished product or semi-product, but exceeds it in size.
The mixture of nonmetallic compounds, the precursors then chemically restore using any applicable methods of obtaining the initial metallic material, without melting the initial metallic material, at stage 48. Used in the present description, the term "without melting" "lack of fusion" and the corresponding concepts mean that the material is macroscopically or in General does not melt so that he went into a liquid state and lost its shape. Can occur, for example, minor localized partial melting, when elements with low melting point melt and diffusion merge with ale is nami with a higher melting temperature, which do not melt. Even in such cases, the General form of the material remains unchanged.
According to one technology, which is denoted by the term "solid recovery" or "recovery in the solid phase, since the non-metallic compound precursor charge in the form of solids, chemical reduction can be carried out by electrolysis in molten salt. Electrolysis in molten salt is a known method described, for example, in published patent application WO 99/64638, the contents of which are incorporated in the present description in its entirety by this reference. Briefly, during electrolysis in a molten salt mixture of non-metallic compounds, the precursors are immersed in the electrolytic cell (the cell) in the electrolyte in a molten salt, such as, for example, chloride salt, at a temperature below the melting temperature of those metals, which form a non-metallic compound precursor. The mixture of nonmetallic compounds, the precursors is the cathode of this cell with the anode. Elements connected to the said metals in a non-metallic compounds-the predecessors, such as, for example, oxygen in the preferred case of the oxide nonmetallic compounds, the precursors are removed from this with the art due to the chemical recovery (i.e., reaction, reverse chemical oxidation). The reaction is carried out at an elevated temperature to accelerate the diffusion of oxygen and other gases from the cathode. The cathode potential is controlled in such a way as to ensure the recovery of non-metallic compounds, the precursors, and not the flow of other possible chemical reactions, such as, for example, the decomposition of the molten salt. The electrolyte is a salt, preferably a salt, which is more stable than the equivalent salt those metals which are cleaned, and in the ideal case - a very stable for the removal of oxygen or other gas to a low level. Chlorides and mixtures of chlorides of barium, calcium, cesium, lithium, strontium and yttrium are preferred. Chemical reduction can be carried out to completion, so that non-metallic compound precursor is fully restored. Instead, chemical recovery may be partial, so that the part of non-metallic compounds, the precursors remains.
According to another technology, which is denoted by the term "vapor recovery" or "recovery in the vapor phase", since the non-metallic compound precursor charge in the form of a vapor or gas phase chemical reduction may be performed by restoring mixtures halo is endow base metal and alloying elements in the liquid alkali metal or liquid alkaline earth metal. For example, titanium tetrachloride and chlorides of alloying elements take the form of gases. The mixture of these gases, taken in appropriate quantities enter in contact with molten sodium, resulting in the metal halide is recovered to a metallic state. The metal alloy is separated from the sodium. This recovery is carried out at temperatures below the melting temperature metal alloy. This technology is more fully described in U.S. patent No. 5779761 and 5958106, the contents of which is hereby incorporated into this description by this reference.
The physical appearance of the original metal material at the end of stage 48 depends on the physical form of a mixture of non-metallic compounds, the precursors in the early stage 48. If the mixture of nonmetallic compounds, the precursors had the appearance of freely-current fine particles, powders, granules, grains or the like, the source metal material also will have the same form, except that it is smaller in size and usually with some degree of porosity. If the mixture of nonmetallic compounds, the precursors is a compacted mass of fine particles, powders, granules, lumps or the like, then the final physical form of the original metal material will usually be somewhat porous metal sponge 60, asana figure 3. External dimensions of a metal sponge is smaller than the size of the compressed mass of non-metallic compounds, the precursors, due to the removal of oxygen and/or other related items on stage 48 recovery. If the mixture of nonmetallic compounds, the precursors is a vapor, then the final physical form of the initial metallic material is usually fine powder, which can be subjected to further processing.
Some of the components denoted by the term "other ingredients-additives can cause difficulties when introducing them into the alloy. For example, there may be no suitable non-metallic compounds, the precursors of such components, or existing non-metallic compound precursor of other components of the additives can be difficult chemical recovered in the way or at the same temperature, which is compatible with the chemical recovery of other non-metallic compounds-predecessors. You may need to other components of the additive in the end was present in the alloy in the form in solid solution elements in the form of compounds formed in the reaction with other components of the alloy or in the form of already reacted essentially inert compounds dispersed throughout the alloy. These others is affected components, additives or their precursors can be introduced from the gas, liquid or solid phase, in accordance with need, using one of the four technologies described below, or other applicable technologies.
According to the first technology other components-take supplements in the form of elements or compounds and mixed with compounds predecessors before stage chemical recovery or simultaneously with it. A mixture of compounds, the precursors and other components-additives processed chemical recovery stage 48, but actually reversed only connection precursor, and other components of the additive are not restored.
According to the second technology other components-take supplements in the form of solid particles, but they are not processed chemical recovery used for the base metal. Instead, they are mixed with the original metal material, which is obtained at the stage chemical recovery, but after stage 48 chemical recovery. This technology is especially effective when the stage chemical recovery performed on the fluid (i.e. turnover) powder compounds predecessors, but it can be performed using pre-compressed mass compounds, the precursors, which results in a spongy mass source IU alicebraga material. Other components of the additive are concatenated with the surface of the powder or the surface of the spongy mass and the inner surface of the pores. Solid particles may not necessarily be the response (reaction) in one or in several stages in case they are precursors to other component-additive.
According to the third technology first get predecessor in the form of particles of a powder or in the form of a sponge by pressing compounds, the precursors of the metal elements. Then the particles or sponge is subjected to chemical recovery. After that, another component additive is applied from the gas phase on the surface (external and internal, if the particles are spongy) particles or on the external and internal surfaces of the sponge. According to one technique, a gaseous precursor or substance in the elemental state (e.g., gaseous methane, nitrogen or borane) to wrap around the surface of the particles or sponge for the deposition of compound or element from the gas to the surface. The materials obtained on the surface, may not necessarily be subjected to the reaction in one or more stages, if they are precursors to other component-additive. For example, boron serves to the surface of titanium by blowing borane above this surface, and the subsequent processing of the besieged borane is subjected to the reaction with the formation of titanium diboride. Gas bearing interest component may be supplied in any suitable way, for example, in the form of commercially available gas or by the generation of gas, for example, by evaporation by electron beam ceramics or metal, or by use of plasma.
The fourth technology is similar to the third technology, except that another component is additive not precipitated from the gas and of the liquid. First get the predecessor in the form of particles of a powder or in the form of a sponge by pressing compounds, the precursors of the metal elements. Then the particles or sponge is subjected to chemical recovery. After that put the other component is additive on the surface (internal and external, if the particles are spongy) particles or on the external and internal surfaces of the sponge, by deposition from the liquid. According to one technique, the particles or sponge dipped in a liquid solution of the compound-predecessor of another component of the additive in order to cover the surface of the particles or sponge. The connection is a predecessor of another component of the additive is subjected to a second chemical reaction in order to leave the other component is additive to the surfaces of the particles or on the surfaces of the sponge. For example, in an alloy based on titanium can be introduced lanthanum by covering surfaces of recovered particles and sponge (obtained from compounds predecessors) lanthanum chloride. After that, the coated particles or sponge is heated and/or exposed to vacuum to remove the chlorine, leaving lanthanum on the surfaces of particles or sponge. Optional coated lanthanum particles or sponge can be oxidized to form a thin dispersion lanthanum-oxygen with oxygen from the environment or from solution in the metal, or coated with lanthanum particles or sponge may be subjected to reaction with another element, such as, for example, sulfur. According to another technology component-additive applied on the particles or on the sponge electrochemical method. According to another technology particles or sponge can be immersed in a bath containing the other component is a Supplement extracted from this bath, and any solvent or carrier is evaporated to leave a coating on the surface of particles or sponge.
Whatever recovery method may be employed at step 48 and no matter how introduced another component-additive, the result is a mixture that contains the entire composition of the alloy. Ways of introducing other components of the additives can be carried out on the predecessors before recovery component of the base metal or already restored the material. In some circumstances, a metal alloy can be freely current particles, and in other cases may have a sponge-like structure. Lips is athay structure is obtained using the solid-phase recovery if the connection predecessors were pre-pressed before the actual chemical recovery. Compound precursor can be pressed with the formation of the pressed mass, which is larger than the desired finished metal product.
The chemical composition of the original alloy metal is determined by the types and amounts of metals in the mixture of nonmetallic compounds predecessors, taken on the steps 40 and 42, and other components-additives that are introduced into the process. The relative amounts of the metal elements are determined by their respective proportions in the mixture at the stage 44 (and not on the respective ratios of the compounds, and the corresponding ratios of the metal element). In the case of greatest interest, the source metal alloy contains more titanium than any other element, as the base metal, giving the original metal alloy based on titanium. Other interest base metals include aluminum, iron, Nickel, cobalt, ferro-Nickel, an alloy of iron-Nickel-cobalt and magnesium.
The source metal alloy is typically in the form, which is not structurally suitable for most applications. Accordingly and preferably, the source metal alloy after this the compacted with getting compacted metal products, moreover, without melting the initial metallic alloy material and without melting the consolidated metallic products, the stage 50. Seal eliminates the porosity of the initial metallic alloy, preferably increasing its relative density to 100% or close to this value. You can use any applicable type seal. Preferably the seal without binding, which is an organic or inorganic material that can be added to the powder to facilitate adhesion of the powder particles with each other during the compaction process. A binder may leave an undesirable residue in the target structure, and therefore its use should preferably be avoided.
Preferably, the seal 50 performing hot isostatic pressing of the original metal alloy under appropriate conditions as temperature and pressure, but at a temperature below the melting temperature of the source metal alloy and compacted metal products (and these melting points are usually the same or very close to each other). Can also be used in methods of pressing, solid-phase sintering and extrusion in the shell, in particular in the case when the source metal alloy has the form of a powder. Compaction leads to the reduction of the external dimensions of the mass of the source is about the metal alloy, but this reduction in size is predictable when you have experience working with specific compositions. The process 50 of the seal can also be used to provide further alloying metal products. For example, the shell used in hot isostatic pressing, may not be removed, so that there is a residual content of oxygen and nitrogen, or the shell may be injected carbon-containing gas. After heating for hot isostatic pressing, the residual oxygen, nitrogen and/or carbon diffuses into the alloy based on titanium and legeret it.
Sealed metal product, such as shown in figure 1, can be used in its compacted state. However, in appropriate cases, sealed metal product may optionally be subjected to further processing, step 52. Subsequent processing may include molding (pressure treatment) applicable to any metal way, for example, forging, extrusion (extrusion), rolling (rolling), etc. Some metal compounds are amenable to such forming operations, others do not. Sealed metal product at the stage 52 may additionally or instead not necessarily be subject to other customary during the machining operations. Such subsequent the I processing may include, for example, heat treatment, surface coating, mechanical dimensional processing, etc.
The metal material is never heated above its melting temperature. Additionally, it can be kept below a particular temperature, which themselves below the melting temperature. For example, when two-phase alpha-beta alloy based on titanium is heated above the temperature of polymorphic transformation in beta ("beta transus"), formed the beta phase. The beta phase is transformed into the alpha phase when the alloy is cooled below the temperature of transformation in the beta phase. For some applications it is desirable that the metal alloy is not heated above the temperature of transformation in the beta phase. In this case, take precautions so that the alloy in the form of a sponge or other metallic state is not heated above its temperature of transformation in the beta phase at any stage during the entire process. The result is a fine microstructure, which is free from colonies alpha phase and which can more easily impart superplasticity than coarse microstructure. Due to the small size of the particles resulting from such processing requires less effort to achieve the fine structure in the final product, which reduces the cost of the product. Subsequent manufacturing operation panel is placed due to low voltage plastic flow of the material, therefore, it is possible to use smaller and cheaper forging presses and other metal processing equipment, and such equipment less wear.
In other cases, such as, for example, some of the details and design of the fuselage, it is desirable to heat the alloy above the temperature of transformation in the beta phase and later in the beta-phase region to have a beta phase and has improved impact strength (strength) of the final product. In this case, the metal alloy during processing can be heated to temperatures exceeding the temperature of transformation in the beta phase, but in any case not higher than the melting temperature of the alloy. When the product is heated above the temperature of transformation in the beta phase, again cooled to temperatures below the temperature of transformation in the beta phase, and a thin structure of the colonies, which can complicate the ultrasonic testing of the product. In this case, it may be preferable to manufacture the product and subjected to the ultrasonic testing at low temperatures without heating to temperatures above the temperature of transformation in the beta phase, tekstovi it was free from colonial status. After completion of the ultrasonic inspection carried out to certify that a product has no field inhomogeneity, the product can be subjected to heat treatment at temperature the round above the temperature of transformation in the beta phase, then cool. The finished product is less amenable to control than a product that is not heated above the temperature of transformation in the beta phase, however, no areas of heterogeneity has been installed previously.
The type of microstructure, morphology and scale of the product are defined by the source materials and processing. Grain products, produced according to the proposed technology, in General, correspond to the morphology and particle size of the powder raw materials in the case, when applying the method of solid-phase recovery. Thus, 5-micrometer particles of the precursor to give the final grain size of the order of about 5 micrometers. For most applications, it is preferable that the grain size was less than about 10 micrometers, although the grain size can reach up to 100 micrometers or more. As described above, the proposed technology is applied to alloys based on titanium allows you to avoid patterns of alpha colonies emerging from the transformed large beta grains, which under normal, based on the melt processing occur during cooling of the melt to the beta-phase region of the phase diagram. According to the proposed technology metal never melts and is not cooled from the melt to the beta-phase region, so large grains beta phase never occurs. Grain beta-FA is s can be obtained by subsequent processing, as described above, but get them at a lower temperature than the melting point and, therefore, they are much smaller beta grains that occur during cooling from the melt, as in usual practice. In normal, based on the melting practice subsequent processes of Metalworking designed for destruction and globularization gross alpha structure associated with the structure of the colonies. According to the proposed technology, this treatment is not required because the resulting structure is thin and does not contain alpha-plates.
The proposed technology allows to translate a mixture of non-metallic compounds, the precursors in the finished metallic state without having to metal finish metallic state ever was heated above its melting point. Consequently, this process avoids the costs associated with the operations of melting, such as, for example, the cost of the furnace with controlled atmosphere or vacuum furnace in the case of alloys based on titanium. Microstructure associated with melting, i.e. conventional coarse-grained structure and the resulting casting discontinuities are absent. Without such inhomogeneities products can be made lighter in weight, because the additional material introduced to compensate for such irregularities can leave the ü. A lot of confidence in achieving free of discontinuities condition of the product due to better ability to control, as described above, also leads to a reduction in the excess material, which otherwise should be applied. In the case susceptible to this phenomenon of two-phase alloys based on titanium, reducing or preventing the formation of alpha-shell" due to restoring the environment. Improved mechanical properties, such as static strength and fatigue strength.
Although the above was described in detail specific embodiments of the present invention for purposes of illustration, may be made of various modifications and changes without going beyond the spirit and scope of the present invention. Accordingly, the present invention is not limited by anything except the attached claims.
1. The method of obtaining articles of base metal doped alloying element, comprising: a step of preparing a mixture of non-metallic compounds-the predecessor of the base metal and non-metallic compounds-the predecessor of the alloying element, through the implementation stage of the availability of chemically recovered non-metallic compounds-the predecessor of the base metal and chemically recovered metallicheskogo connection predecessor of the alloying element, stage chemical recovery compounds, the precursors of the metal alloy, without melting the metallic alloy, the step of introducing one or more than one component of the additive and the step of sealing a metal alloy with obtaining compacted metal products without melting, at this component, the additive is introduced during mixing or during chemical recovery, or after stage chemical recovery, and as a component-additive use element, a mixture of elements or chemical compound, under this component, the additive is dissolved in the matrix or forms a discrete phase in the microstructure of the alloy and is not restored on the stage chemical recovery.
2. The method according to claim 1, comprising the additional step of reacting the component outs.
3. The method according to claim 1, wherein the step of ensuring the availability of chemically recovered non-metallic compounds-the predecessor of the base metal includes the step of selecting as the base metal of titanium, aluminum, iron, Nickel, ferro-Nickel, alloy of iron-Nickel-cobalt or magnesium.
4. The method according to claim 1, wherein the step of preparing includes the step of introducing component-additive in the form of an element, a mixture of elements or compounds and mixing this component is additive pack is mentioned compounds predecessor.
5. The method according to claim 1, in which stage chemical recovery includes the step of mixing the solid particles containing the component-additive, with the said metal alloy.
6. The method according to claim 1, in which stage chemical recovery includes the step of the deposition component of the additive from the gas phase to the surface of the metal alloy.
7. The method according to claim 1, in which stage chemical recovery includes the step of the deposition component of the additive from the liquid phase to the surface of the metal alloy.
8. The method according to claim 1, wherein the step of providing a chemically recovered non-metallic compounds-the predecessor of the base metal includes the step of providing a chemically recovered nonmetallic compound of the base metal in finely dispersed solid form, and the step of providing a chemically recovered non-metallic compounds-the predecessor of the alloying element includes the step of providing a chemically recovered non-metallic compounds-the predecessor of the alloying element in fine particulate form.
9. The method according to claim 1, wherein the step of providing a chemically recovered non-metallic compounds-the predecessor of the alloying element includes the step of providing connection-predecessor of such alloying cell battery (included) is that, which is a thermophysical incompatible with alloying with the base metal.
SUBSTANCE: method includes heating of charge, containing oxygenous or oxygenous and oxygen-free composition of tantalum or niobium and halogenide of alkali metal with formation of melt. Into melt it is introduced alkali metal at blending and it is implemented reduction of tantalum or niobium at temperature 550-850°C. Additionally amount of oxygen in melt is regulated by means of changing of ratio of components of harge according to relation where n(O) - amount of oxygen, mol, k - empirically determined coefficient, k=60-350 mol, m1 and M1 - mass and molar mass of oxycompound of tantalum or niobium correspondingly in kg and kg/mol, m2 and M2 - mass and molar mass of oxygen-free composition of tantalum or niobium correspondingly in kg and kg/mol, m3 and M3 - mass and molar mass of alkali metal halogenide correspondingly in kg and kg/mol.
EFFECT: increased purity of powder, increasing of its specific surface area.
5 cl, 1 tbl, 7 ex
SUBSTANCE: double complex chlorides of ittrium and potassium is reduced by lithium at temperature 450-720°C in inert atmosphere and high pressure. Received reacting mass is heated at a rate 3-5°C/min up to the temperature for 60-300°C higher the reduction temperature and then it is implemented vacuum separation at a temperature 750-780°C and evacuation 1·10-4 millimetres of mercury.
EFFECT: it is provided receiving of microcrystalline metallic powder of itrrium with minimal content of oxygen and gas-producing admixtures, described by high dispersity.
5 cl, 1 tbl, 1 dwg, 1 ex
SUBSTANCE: invention concerns rare-metal industry. Particularly it concerns receiving of metallic tantalum by metallothermic reduction of its salts. For receiving of metallic tantalum charge, containing mixture of double complex chloride salt of tantalum - KTaCl6 and potassium chloride - KCl in ratio 1:(0.2÷0.5) by mass are fed by portions or uninterruptedly in the form of powder or melt on melt mirror of metallic sodium, taken in excess 60-80% of stoichiometrically necessary amount. Reduction is implemented at temperature 550-650°C, with speed of charge feeding 15-20 g/cm2·hour of area melt mirror of metallic sodium melt. Received reduced reactionary mass is subject to vacuum- thermal processing at temperature 500-540°C and residual pressure, not exceeding equilibrium pressure of sodium steams at temperature of vacuum- thermal processing of unreacted sodium. After vacuum- thermal processing it is implemented hydro metallurgical treatment of reactionary mass.
EFFECT: exclusion of ecological pollution of environment.
4 cl, 2 tbl, 2 ex
SUBSTANCE: method includes reduction of fluorine tantalite of potassium with liquid sodium in medium of melted saline bath of halogenides of alkali metals by means of alternate portioned dozing of sodium, and further - of fluorine tantalite of potassium. Fluorine tantalite of potassium is introduced into mixtures with part of the charge of halogenides of alkali metals, used for making of a saline bath. Amount of halogenides of alkali metals in the mixture introduced into melt with fluorine tantalite of potassium constitutes from 60 to 125% (wt) from weight of fluorine tantalite of potassium.
EFFECT: dimension in size of powder particles, reduction of duration of reduction process, decreasing of power consumption for melting of saline charge and forced cooling of reaction vessel.
1 tbl, 1 ex
SUBSTANCE: invention pertains to procurement of metallic device; in particular, parts for gas turbines of the flying constructions made from titanium alloys. To produce such metallic devices, the following range of procedures must be brought into action. Firstly, one or several non-metallic junction-predecessors should be made ready, each containing metallic composition element therein. These need to be chemically restored to procure a multitude of initial metallic particles, preferably those whose size varies between 0.0254 mm to approximately 13 mm, which do not have to be melted down. After having been fused at a later stage, they will solidify. The melted and solidified metal can be used either as a casting metal product or can be transferred into a partially finished product (billet) to be processed additionally until it is ultimately ready. The invention permits to substantially reduce the frequency of chemical faults in a metal product.
EFFECT: procurement of metal products by means of reconstruction of non-metal junction-predecessors and by fusion with a view to decrease the frequency of any chemical faults.
19 cl, 4 dwg
FIELD: nonferrous metallurgy.
SUBSTANCE: invention relates to manufacturing zirconium powder for making pyrotechnic articles, in particular explosive and inflammable mixtures. By-layers prepared powered mixture of potassium fluorocirconate and alkali metal chloride, preferably sodium chloride, at ratio 1:(0.15-0.6) and sodium metal in amount exceeding its stoichiometrically required amount by 10-20%. Preparation involves grinding of potassium fluorocirconate and alkali metal chloride to fineness below 50 μm as well as preliminary recrystallization of potassium fluorocirconate. Charge is heated to temperature 450-600°C, at which reduction reaction starts and during this reaction reaction mixture heats to 700-800°C and reduction of potassium fluorocirconate takes place. Reaction products are cooled to 400-650°C and freed of sodium through vacuum distillation at residual pressure 1.3-13.3 Pa for 0.5-2.0 h, after which they are discharged from reaction vessel and ground. Zirconium powder is washed with water to remove fluoride and chloride salts and then dried. Zirconium powder contains 95-98% of fine fractions, including fraction below 10 μm in amount 45-55%.
EFFECT: enhanced fineness of prepared zirconium powder end assured fire safety of the process.
8 cl, 3 ex
FIELD: treatment of powdered, especially metal containing initial material introduced together with treating gas such as reducing gas for creating fluidized bed in fluidized bed chamber, for example in fluidized-bed reactor.
SUBSTANCE: treating gas at least after partial conversion in fluidized bed is removed out of fluidized bed and then outside fluidized bed it is partially recovered, preferably oxidized due to performing chemical, namely exothermal reaction with gaseous and(or) liquid oxidizer. Heat energy of such reaction at least partially is fed to fluidized-bed chamber, especially to fluidized bed or it is taken out of it. Cyclone is arranged over fluidized bed in fluidized-bed chamber. Powdered initial material is heated or cooled in zone of cyclone, namely near inlet opening of cyclone due to using treating gas at least partially recovered over fluidized bed in fluidized-bed chamber, possibly heated or cooled, and(or) due to using system for recovering treating gas.
EFFECT: possibility for decreasing caking on distributing collector of fluidized-bed reactor, lowered slagging in zone of fluidized bed.
10 cl, 1 dwg
FIELD: powder metallurgy, possibly production of finely dispersed powder of molybdenum, its composites with tungsten, namely for producing hard alloy materials on base of molybdenum and tungsten.
SUBSTANCE: method provides production of molybdenum and its composites with tungsten at temperature no more than 900°C and also production of materials in the form of finely dispersed powders. Method comprises steps of reducing compounds of molybdenum and tungsten (MoO3 and WO3) by metallic magnesium in medium of melt chlorides such NaCl, KCl or carbonates such as Na2CO3, K2CO3 or their binary mixtures such as NaCl - KCl, Na2CO3 - K2CO3, NaCl - Na2CO3, KCl - K2CO3 at temperature 770 -890°C. According to results of fineness analysis produced powder of molybdenum represents homogenous material having 80% of particles with fraction size 2.2 - 3 micrometers. Composition material depending upon Mo content includes particles with fraction size 5 - 15 micrometers.
EFFECT: enhanced efficiency of method.
1 tbl, 3 ex
FIELD: non-ferrous metallurgy, possibly production of highly purified powders of tantalum and niobium with large specific surface by metal thermal reduction.
SUBSTANCE: method is realized at using as corrosion protection means layer of halide of alkali metal formed on inner surface of vessel before creating in reaction vessel atmosphere of inert gas. Charge contains valve metal compound and halide of alkali metal. It is loaded into reaction vessel and restricted by protection layer of halide of alkali metal having melting temperature higher than that of charge by 50 - 400°C. Before loading charge, valve metal compound and alkali metal halide may be mixed one with other. Mass of protection layer of alkali metal halide Ml and charge mass Mc are selected in such a way that that to satisfy relation Ml = k Mc where k - empiric coefficient equal to 0.05 - 0.5. Gas atmosphere of reaction vessel contains argon, helium or their mixture. Fluorotantalate and(or) oxyfluorotantalate or fluoroniobate and(or) oxyfluoroniobate of potassium is used as valve metal compound. Sodium, potassium or their mixture is used as alkali metal. Chloride and(or) fluoride is used as alkali metal halide. Valve metal compound and alkali metal halide may contain alloying additives of phosphorus, sulfur, nitrogen at content of each additive in range 0.005 - 0.1% and 0.005 - 0.2% of mass valve metal compound respectively. Invention lowers by 1.3 - 2 times contamination of powder with metallic impurities penetrating from vessel material. Value of specific surface of powder is increased by 1.2 - 1.8 times, its charge is increased by 10 - 30 %, leakage current are reduced by 1.2 - 1.5 times.
EFFECT: improved quality of valve metal powder, enhanced efficiency of process due to using heat separated at process of reducing valve metal for melting protection layer.
9 cl, 1 tbl, 4 ex
FIELD: process engineering.
SUBSTANCE: invention relates to methods of producing reinforced steel parts, for example reinforced rings. Proposed method comprises fabricating steel base with cavity in the form of groove, producing hole on said base side and welding branch pipe therein. Then porous half stuff from carbide metal powder is fitted into said groove, and impregnated alloy is fitted on said half stuff, the impregnating alloy having liquidus temperature lower than that of the belt melting. Steel cover is welded to said base on the groove face side by continuous seam, vacuum system is connected to said branch pipe and base cavity is evacuated. Now produced assembly is placed into furnace with its working zone communicated with atmosphere to heat it to temperature exceeding impregnating alloy liquidus temperature and lower than base melting point, and half stuff is infiltrated by impregnating alloy.
EFFECT: higher efficiency, simplified process.
8 cl, 6 dwg, 5 ex
FIELD: process engineering.
SUBSTANCE: invention relates to powder metallurgy, namely to method of producing high-thickness plates from foamed aluminium that can be used in production of elevators, aircraft and ship engineering and construction. Proposed method comprises hot rolling of mix of aluminium alloy powder with porophore into sheet slabs, assembling a stack with interlayer fitted in between sheet slabs and placing assembled stack into mould with sizes of finished product, and foaming. Note here that said interlayer between sheet slab represents mix of aluminium alloy powder with porophore into sheet slabs. Foaming is performed by heating to 40-70°C above the temperature of solid-liquid phase transition. Note also that said foaming is carried out in mold with movable top part in two stages. At first stage foaming is carried out to thickness not exceeding 50% of that required for finished product. At second stage mould top movable part is lifted to allow foaming to thickness of finished product.
EFFECT: higher strength at layers joints and foamed aluminium layer.
3 cl, 2 dwg
FIELD: process engineering.
SUBSTANCE: invention relates to powder metallurgy, particularly to production of composite materials based on Nb intermetallic compound. It can be used in fabrication of parts intended for long operation at high thermal and mechanical loads, for example gas turbine engine high-temperature parts: working and nozzle vanes, fire tubes elements and other components operated at temperatures approximating to 1600°C. Initial powder mix is subjected to mechanical doping in protective atmosphere for 40-50 hours. Then hot isostatic doping is performed at 1450-1550°C and pressure of 25-35 MPa for not over 5 minutes.
EFFECT: uniform structure, high relative density at high yield of suitable material, maximum efficiency.
1 tbl, 3 ex
FIELD: process engineering.
SUBSTANCE: invention relates industrial equipment intended for processing parts in gas atmosphere at simultaneous effects of high pressure and temperature. Proposed gasostatic extruder comprises load bearing base, reactive medium container closed by top and bottom plugs, gas control valves communicated by gas pipelines and made up of body with seat, needle, servo drive, pressure spring and unloading cylinder with its rod arranged on valve needle. Note here that body of every valve has groove to accommodate cylindrical insert connected with gas pipelines. Said insert is made from material insensitive to reactive working medium effects. Note that valve seat is arranged in insert. Unloading cylinder is arranged inside aforesaid spring and coupled with servo drive by quick-release bayonet lock. Said servo drive is jointed to valve body by two pins arranged to adjust needle action on valve seat. Note also that valve incorporates cross piece to lock insert inside aforesaid groove that is fitted in valve body slot. Container top plug has gas inlet.
EFFECT: reliable design, higher safety, antirust protection, reduced weight of container and base.
5 dwg, 3 cl
FIELD: process engineering.
SUBSTANCE: invention relates to industrial equipment intended for processing parts in gas atmosphere at simultaneous effects of high pressure and temperature. Two-chamber gasostatic extruder comprises container with top and bottom plugs that form working chamber, load bearing base, partition dividing said working chamber into outer chamber with neural medium and inner chamber with reactive working medium, system of inert and reactive working media sources with shut-off valves communicated with aforesaid sources, heating and control systems. Said container represents a unit consisting of three thin-wall sleeves pre-assembled with interference fit to produce uniform distribution of compression strains therein in winding high-strength tape on sleeves unit outer surface to make a belt. Inner sleeve surface and top surfaces of top and bottom plugs are furnished with copper coating. Said partition is made thin-walled and tight. Control system can maintain outer chamber neutral medium pressure above working pressure in inner chamber and incorporates device to synchronise pressure in said inner and outer chambers. Said system represents three transducers, interconnected and connected with control system processor.
EFFECT: reliable design, higher safety, antirust protection, reduced weight of container and base.
2 cl, 1 dwg
FIELD: process engineering.
SUBSTANCE: invention relates industrial equipment intended for processing parts in gas atmosphere at simultaneous effects of high pressure (up to 500 MPa) and temperature. Gasostatic extruder comprises container with top and bottom plugs that form working chamber, load bearing base and gas system connected with working chamber. Said container represents a unit consisting of three thin-wall sleeves pre-assembled with interference fit to produce uniform distribution of compression strains therein in winding high-strength tape on sleeves unit outer surface to make a belt. Central sleeve outer surface has multi-start channels for cooling fluid. Note here that antirust coat is applied onto outer sleeve inner surface and central sleeve with cooling channels.
EFFECT: reliable design, higher safety, antirust protection, reduced weight of container and base.
FIELD: process engineering.
SUBSTANCE: invention relates to powder metallurgy, particularly to laser layer-by-layer synthesis. It can be used in machine building to produce complex solid parts from powders to increase their quality and efficiency. Powder metered portions are fed onto working chamber table, powder layer being burnished thereafter. Working chamber is evacuated and laser beam is focused on powder layer. Focused laser beam is moved at preset rate to sinter part sections in layer and mutually perpendicular grid lines that form cells and zones in sintered section. Laser is readjusted and defocused laser beam is used to sinter part section area, light beam diametre and radiation powder being increased.
EFFECT: higher efficiency and quality.
2 cl, 1 ex
SUBSTANCE: tempering method for solid alloy based on tungsten carbide involves alloy heating to the temperature over 1100°C and cooling down in tempering medium. Aqueous solution of polymer based on Termovit-M concentrate with concentration of 2-8% is used as tempering medium.
EFFECT: enhanced operational durability of tools made out of the alloy.
SUBSTANCE: powder composition, containing mixture of magnetically-soft powder of iron or on base of iron, particles of which are surrounded with electric insulating non organic coating and 0.05 to 1.5 wt % of organic lubricant not containing metal and with temperature of evaporation less, than temperature of coating decomposition, is moulded in a die. A moulded ingot is pushed from the die; lubricant is removed by heating in not-reducing atmosphere to temperature above temperature of lubricant evaporation and below temperature of decomposition of non organic coating. Further there is performed heat treatment at temperature between 300°C and 600°C in water steam.
EFFECT: magnetically-soft composite items possess lateral rupture strength 100 MPa, magnetic permeability 700 and losses in core at 1 Tl and 400 Hz.
25 cl, 2 dwg, 8 tbl, 8 ex
FIELD: process engineering.
SUBSTANCE: invention relate to powder metallurgy, particularly to production of iron-based antifriction parts for machine building. Iron-based burden is compacted and sintered to produce sintered parts. Sintered parts are placed in reactor above heated solution of zinc phosphate, reactor is sealed and evacuated to 1 mm Hg. Then the part is dipped into aforesaid solution and kept therein for about one hour. Prior to or after phosphate treatment, calibration is performed. Sintered antifriction part coated with zinc phosphate is impregnated with oil.
EFFECT: longer life of antifriction part in self-lube operation.
4 cl, 1 tbl
FIELD: powder metallurgy, namely apparatuses for pressing powders.
SUBSTANCE: apparatus includes movable and stationary plates, upper and lower punches, pressing block in which die is arranged. Pressing block has two part; upper of said two parts is secured to movable plate and lower part is secured to stationary plate. In one part of block there is additional drive unit for moving punch in plane normal relative to motion direction of movable plate. Pressing block is provided with two carriages placed in guides with possibility of motion in two mutually normal directions. One carriage is arranged in guides of second carriage. Each part of pressing block has four profiled supports. Die is in the form of four shaping members with flat working surfaces. Said members are mounted on profiled supports in such a way that their working surfaces form closed loop. Each member has slit guide normal relative to its working surface and stem mounted in slit guide of adjacent member. Working surface of shaping member coincides with one surface of its stem.
EFFECT: increased density of pressed blanks, enhanced uniformness of density distribution in volume of blank.
2 cl, 4 dwg