Foundry alloy for casting titanium-based refractory alloy ingot
SUBSTANCE: proposed composition contains the following substances, in wt %: tungsten - 28-32, aluminium - 28-32, titanium making the rest.
EFFECT: uniform distribution of tungsten and other dopants to prevent chemical composition liquation, better strength and temperature resistance.
The invention relates to ferrous metallurgy, in particular to the production of master alloys for melting ingot heat-resistant alloy based on titanium.
It is known that nowadays almost all industries, including aerospace, parts and components are operated at high loads and elevated temperatures, so they are often made of titanium alloys. Because titanium alloys generally have complex multi-component chemical composition, we must use good quality ligature. In the smelting of many titanium alloys are used one, and sometimes several ligatures that add to the original in at the beginning of melting or injected directly into the melt liquid titanium, to regulate basic chemical composition of titanium alloy. As is well known in the art, the ligature is a mixture of alloying elements designed to adjust the percentage of the required components in the melt.
Because the chemical composition of the titanium alloy known in advance, it is quite easy to determine the number of ligatures must be added to achieve the desired chemical composition of the melt. However, you should consider whether all the amount of added�Noah ligatures will be completely and evenly distributed in the melt. Therefore one of the main objectives is the development of ligatures, which are easy to melt and evenly distributed in the molten metal.
In the process of doping we have several tasks that need to be addressed.
For example, being in specified chemical composition is complicated by the waste/evaporation of alloying elements in the smelting process. To ensure a uniform distribution of alloying elements is also hindered by the segregation of these elements. Enter refractory elements in the melt is complicated by the fact that they are digested only by means of dissolving, tighten the step and leads to deterioration of material properties.
Known to double and triple ligatures, for example: Al-V, Al-Sn, Al-Mo-Ti, Al-Cr-Mo, which you can use to smelt almost any titanium alloys ("Melting and casting of titanium alloys" Andreev A. L., N. Anoshkin.F. and others. - M.: metallurgy, 1994, p. 127, PL.20 /1/).
In the smelting of titanium alloys it is necessary to ensure sufficiently accurate chemical composition, therefore, the use of double or triple ligatures may lead to excess of the required contents of chemical elements, in particular of aluminum, because of its high content in ligatures.
Known the master alloys for titanium alloys, comprising the following components, �AC.%: molybdenum - 23,99; vanadium - 25,44; aluminium - 49,98; iron - 0,19; silicon - 0,22; carbon - 0,06; oxygen - 0,07; hydrogen - 0,0017; nitrogen - 0,012 (US 3387971, C22C 21/00, 11.06.1968, /2/).
The disadvantage of this ligature is the need for additional introduction of pure refractory metals in the melt, under conditions of vacuum-arc melting quite difficult and can lead to neprotivlenie separate pieces of constituents that contribute to the appearance of such defects as segregation in chemical composition.
One of the most common problems in metallurgy in the smelting of titanium alloys containing tungsten, is its non-uniform distribution due to the high density over the cross section and length of the ingot or billet parts.
Known (RU 2470084 C1, C22C 35/00, 20.12.2012, /3/) ligature for melting heat-resistant titanium alloy containing tungsten 48,0-52,0, titanium 10,0-20,0, hafnium 0,08-0,1, aluminum else. This ligature provides improved strength and heat-resistant properties due to the uniform distribution of tungsten and other alloying elements in the cross section and length of the ingot.
The disadvantage is that the ligature does not provide a sufficient isotropy properties of the alloy and a uniform distribution of alloying elements in it.
And this is necessary when the existing trends in the world - increasing requirements for products and �of Osmania fundamentally new alloys and alloys with improved strength, heat-resistant characteristics.
Task to be solved by the present invention is directed, is the development and acquisition of new ligatures for melting heat-resistant titanium alloys with improved characteristics, with a uniform content of alloying elements in the cross section and length of the ingots (billets) that will avoid segregation in chemical composition.
The technical result of the invention is that the proposed ligature provides uniform distribution of tungsten and other alloying elements in the cross section and length of the ingot, the isotropy properties. This improves the strength and heat-resistant characteristics that directly affect the function of the components of titanium alloy. Also the technical result is the reduction of evaporation/melting loss of the alloying element in smelting process.
On the achievement of specified technical result is influenced by the following essential features.
Ligature for melting ingot titanium alloy based on titanium containing tungsten, aluminum, titanium, characterized in that it contains components in the following ratio, wt. %: tungsten 28-32; aluminium - 28-32; titanium - the rest.
As a result of the development of this ligature is found that the presence of the ligature WOL�frame in this percentage allows you to completely and evenly dissolved in the alloy, that improves the heat resistance of the alloy due to the formation of the structure of dense oxide compounds of tungsten, impairing the permeability of oxygen and hydrogen to the phase boundary at high temperatures and the formation in the surface layer doped solid solutions of titanium-tungsten.
The aluminum content in the ligature in this percentage has a negative impact on the decrease of the melting temperature of the ligature, but it is also important to increase thermal stability of the alloy.
The content of titanium in the ligature in this percentage lowers the melting point of the ligature, forms an intermetallic compound with aluminum, which protects against evaporation and fumes, gives the workability of the alloy (i.e., is a vital link for aluminum and tungsten).
The manufacture of the ligature is carried out in a vacuum arc furnace with a nonconsumable tungsten electrode, before the melting of the charge is placed in a copper water-cooled mold, the furnace is closed and begin pumping out of the oven to a residual pressure of 0.01÷0.05 mm Hg.St.), upon reaching the degree of vacuum in the working space of the furnace SIC argon to a pressure equal to the atmospheric value, then the first phase alloy titanium and aluminum in a proportion that corresponds to the content of these elements in the ligature, to the state, which should lead to a complete dissolution satoumi materials to form a single ingot, at the bottom of the copper mould is placed in the aluminum, and titanium, which have a higher melting temperature, the magnitude of the arc current between the charge and the electrode was 750÷1000 a, While the melting time was 3÷6 minutes, the temperature of the melt 30÷50°C above the liquidus temperature of the alloy Ti-Al, then to the ingot of Ti-Al add the desired amount of tungsten that is placed over an ingot of Ti-Al alloy, and for averaging the chemical composition of the ingot it is removed from the mold, inverted and subjected to re-melting, melt temperature is 1750÷1850°C.
In the embodiment, the manufacture of master alloys for casting refractory titanium alloy, which consists of tungsten, aluminum, titanium, characterized in that it contains these components in the following ratio, wt %: tungsten 28.8; aluminium - 29.1; titanium - the rest. In this case the receipt is carried out in a vacuum arc furnace with a nonconsumable tungsten electrode, before the melting of the charge is placed in a copper water-cooled mold, the furnace is closed and begin pumping out of the oven to a residual pressure of 0.03 mm Hg.St.), upon reaching the degree of vacuum in the working space of the furnace SIC argon to a pressure equal to the atmospheric value, then the first phase alloy titanium and aluminum in a proportion that corresponds to the�corresponds to the content of these elements in the alloy, to the state, which should lead to a complete dissolution satoumi materials to form a single ingot, while the bottom copper crucible placed aluminum, and titanium, which have a higher melting temperature, the magnitude of the arc current between the charge and the electrode 750 a, While the melting time was 4 minutes, the temperature of the melt at 50°C above the liquidus temperature of the alloy Ti-Al, then to the ingot of Ti-Al add the desired amount of tungsten that is placed over an ingot of Ti-Al alloy, and for averaging the chemical composition of the ingot it is removed from the mold, inverted and subjected to re-melting, melt temperature is 1800±10°C.
Thus, the present invention provides a uniform distribution of tungsten and other alloying elements in the cross section and length of the ingot, the isotropy properties. This improves the strength and heat-resistant characteristics that directly affect the function of the components of titanium alloy. Also the technical result is the reduction of evaporation/melting loss of the alloying element in smelting process.
Ligature for melting ingot heat-resistant alloy based on titanium containing tungsten, aluminum, titanium, characterized in that it contains components in the following ratio, wt.%:
SUBSTANCE: titanium alloy contains, wt %: platinum metal 0.01-0.15, rare-earth metal 0.001-0.10 and Ti and impurity - the rest. The titanium alloy preferably includes Co as partial replacement of Ti amounting 0.05-1.00 wt %.
EFFECT: alloy is characterised by high corrosion resistance, good workability.
7 cl, 9 dwg, 4 tbl, 2 ex
SUBSTANCE: mixture is prepared containing maximum 65 wt % of powder produced by plasma spraying of the titanium alloy VT-22, at least 30 wt % of mixture of technical powders of titanium PTM and nickel PNK in ratio 1:1, and 3-5 wt % of received by electrolysis copper powder PMS-1 with size 50 mcm. The produced mixture is pressed at pressure 800-1000 MPa, then sintering in vacuum at temperature at least 900°C for over 1 h is performed.
EFFECT: material production on basis of titanium with high strength.
1 tbl, 1 ex
FIELD: technological processes.
SUBSTANCE: invention relates to rolling and may be used in manufacturing of armoured sheets from (α+β)-titanium alloy. The method to manufacture armoured sheets from (α+β)-titanium alloy includes preparation of charge, melting of a bar with the following composition, wt %: 3.0-6.0 Al; 2.8-4.5 V; 1.0-2.2 Fe; 0.3-0.7 Mo; 0.2-0.6 Cr; 0.12-0.3 O; 0.010-0.045 C; <0.05 N; <0.05 H;<0.15 Si; <0.8 Ni; balance - titanium. Further the bar is shaped into a slab, which is mechanically processed and rolled for semi-finished rolled products, the semi-finished rolled products are cut into stocks and rolled in stages for sheets, and then thermal treatment is carried out.
EFFECT: sheets are characterised by high strength and ballistic properties.
3 cl, 2 dwg, 3 tbl
SUBSTANCE: invention refers to metallurgy, particularly to titanium alloys with enhanced ballistic and mechanical properties. Titanium alloy includes mainly the following components, wt %: aluminium 4.2-5.4, vanadium 2.5-3.5, iron 0.5-0.7, oxygen 0.15-0.19, and the rest is titanium.
EFFECT: titanium-based alloy obtained from recycled materials shows minimum ballistic limit V50 of ca 1848 ft/sec, and high characteristics of yield strength, tensile strength and elongation.
23 cl, 6 dwg, 4 tbl, 1 ex
SUBSTANCE: invention relates to metallurgy, in particular to welded Ti based cast alloys, and intended for manufacturing of the shaped castings of valves, pumps, bodies used in shipbuilding, chemical and other industries. Ti based alloy contains in wt %: 3.0-4.5 Al, 0.02-0.14 C, 0.05-0.14 O, 0.02-0.25 Fe, 0.02-0.12 Si, 0,02-0,15 W, 0.001-0.005 B, Ti and admixtures - rest. Ratios are met: C+O2 ≤ 0.20, 2(V+Fe+Si)/Al ≤ 0.20.
EFFECT: alloy is workable, has good cast properties and set of mechanical properties ensuring operation reliability.
2 tbl, 1 ex
SUBSTANCE: invention relates to metallurgy, namely to titanium materials with high strength and processibility. Titanium material contains iron 0.60 wt % or less and oxygen 0.15 wt % or less, titanium and inevitable impurities are the rest. Material has a non-recrystallised structure formed by processing accompanied by plastic deformation and a recrystallised structure formed by annealing after the above treatment; average size of recrystallised α-grains is 1 mcm or more and 5 mcm or less, and surface area of the non-recrystallised part in a cross section of titanium material is more than 0 to 30%.
EFFECT: material is characterised by high strength and processibility.
2 dwg, 2 tbl, 45 ex
FIELD: process engineering.
SUBSTANCE: invention relates to production of long articles from titanium or its alloy or blanks of such articles. Proposed method consists in preparation of titanium or titanium alloy mix (10), melting said mix by electric arc at scull melting (20), casting of one or several ingots, primarily cylindrical in shape, in diameter smaller than 300 mm from said fused mix (30). Then, said ingots are drawn at 800-1200°C at draw bench (40) for application in, for example, aircraft engineering.
EFFECT: higher quality, simplified production.
13 cl, 3 dwg
SUBSTANCE: alloy contains the following, wt %: titanium 46.3-48.8; aluminium 0.14-2.87, calcium 0.06-1.24; magnesium 0.08-1.61; and iron is the rest.
EFFECT: reducing activation time and increasing alloy sorption capacity.
SUBSTANCE: method to produce titanium blanks involves placement of titanium sponge particles in a press chamber, compaction of the sponge particles to produce a blank, its pressing, removal of dirt from the pressed blank surface, its covering with grease and following rolling. Prior to placing the titanium sponge particles in the press chamber they are heated in a vacuum heating furnace up to the temperature of 700-800°C, alloyed by hydrogen up to the concentration of 0.1-0.9 wt %, then the temperature in the furnace is reduced to the temperature not lower than 300°C, compaction is carried out under the temperature of 300-700°C, compacted blanks are pressed by semicontinuous method via a matrix under the temperature of not more than 700°C with reduction ratio of maximum two and then under the temperature of not more than 700°C and the reduction ratio of maximum three, the blanks are rolled under the temperature of not more than 700°C, with following annealing in vacuum under the temperature of not less than 700°C.
EFFECT: possibility to process hardly deformable titanium under lower temperatures, improved mechanical properties of produced blanks.
SUBSTANCE: titanium aluminide alloy Ti3Al contains, wt %: Al 13-15, Nb 3-6, V 2-4, Zr 0.5-1.0, Mo 1-3, Sn 0.5-3, Si 0.1-0.3, Ti - the rest. A titanium aluminide alloy Ti3Al blank is subject to thermal hydrogen processing by hydrogen saturation followed by vacuum annealing. The hydrogen saturation of the blank is carried out to the concentration of 0.4-0.6 wt % at two stages, and then the blank is rolled. Vacuum annealing is two-staged at residual pressure no more than 5·10-5 mmHg.
EFFECT: heat-resistant titanium aluminide alloy Ti3Al is characterised by high plasticity and heat-resistance.
2 cl, 1 tbl
FIELD: mechanical engineering; piston internal combustion engines.
SUBSTANCE: invention relates to valve of internal combustion engine, method of its manufacture and heat-resistant titanium alloy used for manufacture of valve consisting of following components, mass %: aluminum 7.5-12.5; molybdenum 1.6-2.6; zirconium 1.4-2.4; silicon 0.1-0.2' yttrium 0.005-0.1; titanium - the rest. It has α+α2+β phase composition with intermetallide α2 phase on Ti3Al base dispersed in α phase. Proposed method includes forming of valve from cylindrical blank by deformation machining with preliminary heating and subsequent heat treatment. Preliminary heating of part of blank related to rod done to temperature 5-20oC lower than temperature of complete polymorphic transformation of alloy, and its deformation machining is carrying out by wedge cross rolling. Deformation machining of part of blank related to head is done by forging with preliminary heating to temperature 5-50oC higher than temperature of complete polymorphic transformation of alloy corresponding to beginning of forging, and forging is finished at temperature lower than complete polymorphic transformation of alloy to form plate head of valve and transition section provided smooth changing of head into rod. Invention provides designing of valve, method of its manufacture and heat-resistant alloy used in manufacture of valve making it possible to operate valve within operating temperature range owing to increased long-term strength and creep resistant of valve head material and increased strength, modulus of elasticity and hardness of valve rod material.
EFFECT: improved quality of valve and increased reliability in operation.
16 cl, 3 tbl, 1 ex, 15 dwg
FIELD: powder metallurgy, namely sintered titanium base alloys used as constructional materials.
SUBSTANCE: sintered titanium base alloy contains, mass. %: aluminum, 5.5 - 7.0; zirconium, 1.4 -2.5; molybdenum,, 0.5 - 1.8; vanadium,, 0.8 -2.3; titanium, the balance. Alloy is prepared of powder of said content with particle size in range 0.5 - 3.0 micrometers. Structure of particles includes martensite α - phase and ω-phase with coherent dissipation range 300 - 600 Å. Percentage density of alloy - 99.6%. In structure of alloy there is no α2 - phase. Alloy is prepared by compacting under pressure 1200 Mpa, sintering at 1523 K for 3 hours in vacuum 0.0133 Mpa, annealing at 723 - 823 K for 1.5 hours and cooling together with furnace until room temperature.
EFFECT: enhanced mechanical properties of alloy.
FIELD: metallurgy, namely processes for forging titanium alloys and blank of such alloy suitable for forging.
SUBSTANCE: method comprises steps of preparing blank and forging it. Forging is realized at providing mechanical hardening factor equal to 1.2 or less and at difference of hardness values between central (along width) zone and near-surface zone equal to 60 or less by Vickers. Factor of mechanical hardening is determined as HV(def)/HV(ini), where HV(ini) - hardness of titanium alloy blank before forging; HV(def) -hardness of titanium alloy blank after forging at forging reduction 20%. Forging may be realized at deformation rate from 2 x 10 -4 s -1 to 1s-1 while keeping relations (T β - 400)°C ≤ Tm ≤ 900°C and 400°C ≤ Td ≤ 700°C, where Tβ (°C) -temperature of β-phase transition of titanium alloy, T m(°C) - temperature of worked blank; Td(°C) - temperature of die set. Blank has factor of mechanical hardening 1.2 or less and difference of hardness values between central (along width) zone and near-surface zone equal to 60 or less by Vickers.
EFFECT: possibility for forging titanium alloy blanks at minimum difference of material properties along depth, simplified finishing of blank surface after forging, reduced cracking of blank material, good workability of blank with favorable ductility and fatigue properties.
8 cl, 5 tbl, 6 dwg, 4 ex
SUBSTANCE: invention proposes titanium-base alloy and article made of thereof. Alloy comprising aluminum, molybdenum, vanadium, chrome, iron, zirconium, oxygen, carbon, hydrogen, nitrogen, copper and nickel comprises additionally silicon and tungsten in the following ratio of components, wt.-%: aluminum, 2.0-6.8; molybdenum, 1.0-3.5; vanadium, 3.0-6.0; chrome, 0.4-1.6; iron, 0.2-1.2; zirconium, 0.01-0.3; oxygen, 0.04-0.14; carbon, 0.02-0.1; hydrogen, 0.003-0.02; nitrogen, 0.005-0.05; copper, 0.001-0.1; nickel, 0.001-0.01; silicon, 0.02-0.15; tungsten, 0.001-0.03, and titanium, the balance. Invention provides the development of titanium alloys designated for making plane stringers, ribs, frames, fuselage, wings and engines and for applying as material for welding. Invention provides enhancing strength and crack-resistance of the basic alloy and welding joints and reducing article mass.
EFFECT: improved properties and quality of alloy.
3 cl, 2 tbl, 3 ex
FIELD: non-ferrous metallurgy; methods of titanium alloy bricks production.
SUBSTANCE: the invention is pertaining to the field of non-ferrous metallurgy, in particular, to the brick made out of α+β titanium alloy and to a method of its manufacture. The offered brick consists of the following components (in mass %): aluminum - 4-5, vanadium - 2.5-3.5, iron - 1.5-2.5, molybdenum - 1.5-2.5, titanium - the rest. At that the alloy out of which the brick is manufactured, contains - 10-90 volumetric % of the primary α-phase. The average grain size of the primary α-phase makes 10 microns or less in a cross-section plain parallel to the brick rolling direction. Elongation of grain of the primary α -phase is the four-fold or less. The offered method of manufacture of the given brick includes a stage of a hot rolling. At that before the stage of the hot rolling conduct a stage of the alloy heating at the surfaces temperature (Tβ-150)- Tβ°C. During realization of the stage of the hot rolling the surface temperature is kept within the range of (Tβ-300)-( Tβ -50)°C, and the final surface temperature, that is a surface temperature directly after the last rolling, makes (Tβ-300)-( Tβ-100)°C, where Tβ is a temperature of α/β-transition. The technical result of the invention is formation of a brick out of the high-strength titanium alloy having a super pliability, excellent fatigue characteristics and moldability.
EFFECT: the invention ensures production of a brick out of the high-strength titanium alloy having a super pliability, excellent fatigue characteristics and moldability.
7 cl, 7 dwg, 21 tbl, 2 ex
FIELD: nonferrous metallurgy; aircraft industry; mechanical engineering; development of alloys on the basis of titanium.
SUBSTANCE: the invention is pertaining to the field of nonferrous metallurgy, in particular, to development of alloys on the base of titanium, working at the heightened temperatures. It may be used in an aircraft industry for manufacture of components, for example, disks, vanes, rings, and also in mechanical engineering. The invention presents an alloy based on titanium and a hardware product produced out of it. The alloy contains aluminum, zirconium, stannum, niobium, a molybdenum, silicon, carbon and oxygen. At that it in addition contains tungsten and iron, at the following ratio of components (in mass %): aluminum 5.8 - 6.6, zirconium 2.0 - 4.0, stannum - 2.5 - 4.5, niobium - 0.8-2.5, molybdenum - 0.8- 1.5, silicon - 0.25-0.45, carbon - 0.05-0.1, oxygen -0.05-0.12, tungsten - 0.35-0.8, iron - 0.06-0.13, titanium - the rest. The technical result is a development of an alloy having the lower weight at the given short-time strength and a specific low-cycle fatigue, that increases an operational life and reliability of the components of the hot tract of aero-engines.
EFFECT: the invention ensures development of an alloy with the lower weight at the given short-time strength and a specific low-cycle fatigue with increased operational life and reliability.
2 cl, 2 tbl, 3 ex
FIELD: medicine; instrument-making industry; radio industry; production of materials with a memory effect of the form.
SUBSTANCE: the invention is pertaining to the materials with a memory effect of the form and with the modified surface, which may be used as implants in medicine and as the temperature sensors, thermo-sensitive and executive elements and designs in instrument-making industry, the radio industry. The offered material consists of a base made out of a titanium nickelide of the following composition (in at. %): titanium - 49-51, nickel - the rest, and the surface layer modified by alloying elements. The modified surface layer is formed by irradiation with a low-energy high-current electronic beam and has a depth of 1000-2500 nanometers and the dimensions of the crystal grains of no more than 30 nanometers. In the capacity of the alloying elements it contains oxygen and carbon at the following ratio of components (in at. %): oxygen - 10-20, carbon - 10-15, titanium - 40-50, nickel - the rest. The technical result of the invention is production of the materials with an effect of memory of the form and a high degree capability of the form restoration both at a low and high deforming loadings.
EFFECT: the invention ensures production of the materials with an effect of memory of the form and a high degree capability of the form restoration both at a low and high deforming loadings.
1 tbl, 1 ex
FIELD: metallurgy, in particular, titanium-based materials resistant to change of color.
SUBSTANCE: construction material of pure titanium contains, wt%: Fe 0.08 or less; Nb 0.02 or less; Co 0.02 or less, and is provided with surface oxide film having thickness of 170Å or less. Method involves producing material from pure titanium; etching and heating to temperature X( C) within the range of from 130 C to 280 C for time T (min) satisfying condition of T≥239408xX-2,3237.
EFFECT: increased resistance to change of color for prolonged time as compared to traditional materials.
3 cl, 2 dwg, 4 tbl, 3 ex
SUBSTANCE: invention relates to titanium-base alloys used in making high-strength and high-efficient articles. Titanium-base alloy consists of aluminum, vanadium, molybdenum, iron and oxygen. Components of alloy are taken in the following ratio, wt.-%: aluminum, 3.5-4.4; vanadium, 2.0-4.0; molybdenum, 0.1-0.8; iron, max 0.4; oxygen, max 0.25, and titanium, the balance. Invention provides the development of universal alloy for large-sized forged pieces and stamps, thin-sheet roll and foil possessing the necessary strength and plastic indices and structure.
EFFECT: improved and valuable properties of alloy.
FIELD: metallurgy; high-strength alpha-beta alloys.
SUBSTANCE: Specification gives versions of titanium-based alpha-beta alloys. The proposed alloy contains the following components: aluminum, 4.5-5.5; vanadium, 3.0-5.0; molybdenum, 0.3-1.8; iron, 0.2-0.8; oxygen, 0.12-0.25; by-elements and admixtures, lesser than 0.1 each; total amount of by-elements and admixtures is lesser than 0.5; the remainder being titanium.
EFFECT: high strength of alloy, good workability and ballistic properties.
4 cl, 5 tbl, 3 ex