Production of long articles from titanium

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

 

The invention relates to a method for the production of elongated articles of titanium, or titanium alloy, or pieces of such products.

The term "elongated product" here means the metal part, the dimensions of the cross section which is significantly less or even much less than its length.

Long products include metal parts, the production of which usually involves at least one drawing operation. However, the definition of the extended product is not solely limited to such details.

Under long products often involve metal parts produced during the operation of the drawing, and profile details, including hollow profiles, and tube.

The term "procurement" should here be understood in a rather broad sense. It means an elongated product, not the end, as such, the General form of which mainly takes the General form of the end of the elongated product. This means that the workpiece is elongated product is elongated metal part.

This does not preclude any subsequent molding of this procurement, for example, by machining or modification of this General form, for example, by bending, folding, or any other plastic deformation.

It should be understood that the procurement of the elongated product is: is using elongated, which may be subjected to various kinds of processing, such as molding, machining or surface treatment to obtain the final product.

Applications of elongated products from titanium or titanium alloy numerous. In particular, they include the aviation and aerospace construction.

There are certain rules governing the metallurgical quality of the products. The required quality depends on the intended application.

For example, for aircraft construction requires high quality because of the serious consequences that entails inadequate quality of the product.

Compliance with the established quality standards is not limited to the field of aviation: in practice, most applications require compliance with minimum steel quality to determine whether they are normal or not. And obtaining high-quality products is not limited to aviation and aerospace fields.

Requirements regarding quality today added requirements for price and availability, which are almost as important. In other words it's not enough to get a product that meets the quality requirements, it is necessary to achieve a satisfactory value and sufficient to satis the creation of the market.

Therefore constantly looking for the least expensive method of production, which will allow you to get the product at least equivalent quality.

Traditional methods begin with the preparation of titanium containing sponge titanium, titanium shavings, waste titanium (sometimes mistakenly referred to as 'scrap titanium") and/or most often secondary titanium.

This mass of titanium then melt and meld into a single ingot of considerable diameter.

In these traditional methods can be applied to various technologies for the implementation of melting/casting weight titanium.

Melting through bombardment by electrons, also referred to the English expression "Electron beam furnance" ("electron-beam furnace"), is used for melting a mixture of titanium sponge and secondary material (waste) as the primary material. Secondary materials are less expensive than the titanium sponge, which implies that economic interest, which can be obtained by this method.

Melting through the plasma torch and melting through bombardment by electrons in a cold crucible are more recent technologies that allow more continuous casting and allow to melt larger quantities of waste titanium. These technologies are also more economic the tion, than melting through traditional bombardment by electrons.

When traditional methods of melting, casting the molten material is gradual and rather slow. Typically, the molten material is gradually poured in the foundry crucible due to the overflow melting pot, as the material melts. The duration and phasing of the wheels, mainly because of the limitations of the technology of smelting, lead to casting defects in the ingot.

To meet the high requirements for metallurgical quality, for example, the critical parts of the field of aviation, it is necessary to melt the ingot obtained after primary smelting/casting, and pour again. Subsequent melting ultimately improve the metallurgical quality of the ingot.

Traditionally melting/casting is carried out according melting technology by means of vacuum arc, also referred to as "VAR" (from the English "vacuum arc remelting (vacuum arc remelting")). The ingot obtained after the first heat, is an electrode, which should be gradually melted and simultaneously cast into an ingot of similar diameter in a continuous way. In practice, the diameter of the new ingot on average, 10-20% greater than the diameter of the electrode, that is, primary ingot.

It should be noted that certain standards, such to the to the U.S. standard AMS 4945, used in the field of aircraft construction, require melting "VAR".

This "dual fusion" is expensive. Also the casters is usually taken to cast ingots of large diameter, between about 500 and 1000 mm, since the cost per unit mass decreases with increasing diameter of the cast ingot. In other words, the larger diameter ingots are less expensive for a given amount of material used.

To get rid of the drawbacks of conventional technologies (primary) melting, which mainly is the slowness and phasing melting/casting, was later applied technology of smelting by vacuum arc skull melting method, also referred to by the English term "skull melting" (literal translation from French is "melting in the crust"). By skull melting reach the melting method, in which the crucible is cooled so that above it formed a layer of molten material, in this case, titanium, or the additional crucible, isolating the rest of the molten material from the crucible.

The part of the mass of Titan, is to be applied, is placed in the crucible, while the other part of this mass fulfills the function of the applied electrode. The whole mass of titanium is melted due to the electric arc formed between the y electrode and the crucible, and then heat-treated in a molded tub. Then the molten mass is molded in one or more casting molds at one time by tilting the crucible.

Skull melting allows you to quickly flick at one time, by one party (the slope) of the entire mass of molten material. This may allow you to avoid casting defects associated with slowness and phasing older smelting technology.

Economic considerations usually to pour one big lump.

Skull melting equally allows melting both pieces of titanium and secondary material.

An additional advantage is that the waste rock, which is formed in contact with the crucible, can be easily, i.e. directly reused as a new electrode.

For most of the required elongated product features modern mills is not possible to directly drag the ingots obtained after melting "VAR" or skull melting because of too large diameter ingot.

One or more operations to reduce diameter by forging to transform the ingot of large diameter in one or several discs of suitable diameter for wire drawing mill and for the desired elongated product.

As an example, CL is current, obtained through technology "VAR" or skull melting, can have a diameter of about 600 mm and can be transformed by the subsequent operations of forging ingots with a diameter of about 120 mm, i.e. the reduction of the diameter of the through forging is about 25 times (2500%).

It should be noted that forging definitely improve the metallurgical quality of the discs, thus systematically used after melting (VAR, skull melting, and others).

Additional operations, such as machining to remove a thin surface layer of forged blanks or "Stripping") or the final treatment, if necessary, can be carried out before drawing.

In the end, the usual set of steps in the production of long products of high quality titanium or titanium alloy, since the mass of titanium, includes the following operations, in which:

- melted mass of titanium or titanium alloy and poured a single ingot of large diameter;

- mold technology "VAR" this ingot into a single ingot well as large diameter; this stage is almost mandatory if its not melting was carried out by skull melting; this facility may be required according to aviation standards.

- from an ingot of large diameter g is tovat one or more blanks for drawing, performing one or more operations of forging;

- carry out the drawing of the bars by drawing mill for receiving elongated articles almost final form;

Can then be executed one or more operations of surface treatment and/or change the General appearance of the elongated product to obtain the final of the elongated product.

This set of production steps is not entirely satisfactory, in particular with regard to cost, duration of production of elongated products, as well as with respect to the availability of finished products.

Applicants have found a way to improve the situation.

The proposed method is a method of making elongated articles from titanium or a titanium alloy, or pieces of such products, including the preparation of the mass of titanium or titanium alloy, the melting of the mass by means of an electric arc and the way skull melting, pouring in one or more ingots mainly of cylindrical form and of a diameter less than approximately 300 mm from the molten mass, and then drawing one or more of these bars at a temperature between 800°C and 1200°C by drawing mill.

This method allows to obtain intact elongated product, i.e., practically devoid of all defects in the casting, and its mechanical so the spine, in particular measured by the test gap, at least equivalent to the products that are the result of traditional or known at present. For example, this method allows to receive elongated items, comparable in quality to the products corresponding to the current aviation standards, at least concerning the mechanical strength, for example, U.S. standards AMS or AMS 4935 4945.

In addition, this method offers a potentially lower cost of production compared to conventional or known in the present as well as a shorter duration of production, partly due to the absence of any forging operations, and in General, a significant decrease in the diameter of the ingot which is discharged before the drawing operation, which allows the simultaneous casting of a few bars.

The proposed method improves the availability of the resulting elongated products, in particular by simplifying the set of stages of production and possible use in preparing the mass of titanium or titanium alloy large proportion of recycled material.

Other differences and advantages of the invention are revealed in the study of the following detailed description and the accompanying graphic material on which:

- Fig.1 shows the block diagram, the sludge is utriruya method according to the invention,

- Fig.2 shows a block diagram illustrating one variant of the method according to Fig.1,

- Fig.3 shows a flowchart illustrating an additional method that can be implemented in addition to the methods of Fig.1 and 2.

The accompanying graphic materials can not only serve as a Supplement to the invention, but also, if necessary, to contribute to its definition.

In Fig. 1 shows a method of making elongated articles from titanium or a titanium alloy, or pieces of products of this type.

The method according to Fig. 1 includes an operation preparation 10 weight titanium or titanium alloy, the melting operation 20 of this mass by means of an electric arc skull melting method, the operation of the wheels 30 of the molten mass of one or more ingots mainly cylindrical shape and a diameter of less than about 300 mm, then the operation of the lug 40 of one or more bars at a temperature between 800°C and 1200°C by drawing mill. Optional obtained at this stage of the drawing, an elongated product can be subjected to one or more final or intermediate stages of processing 50.

The method according to Fig.1 begins with the preparation of the mass of the titanium or titanium alloy 10. The chemical composition of this mass corresponds to the desired grade of the elongated product. For example, a chemical with the becoming of this mass can be designed to produce alloy TA6V4, or equivalent, such as specified in the U.S. standard AMS 4935, or TA3V2.5, or the equivalent, such as specified in the U.S. standard AMS 4945.

These alloys are particularly used in the field of aviation, in which stringent standards require high metallurgical quality products. Their use in no way limited to this industry. And the implementation of the method according to Fig.1 is also not limited specifically, these alloys, but on the contrary extends to many different titanium compounds, according to it is used for the intended application, for example t, KZT60, or other.

This mass may include sponge titanium, waste titanium or titanium alloy, called in English "scrap" ("Lom"), shavings of titanium or titanium alloy, all or part of the peel, shell, or waste rock resulting from the skull melting, or most often secondary titanium in any form. The composition of the recycled material is controlled as to its quality and chemical composition.

Secondary elements can occur from initially laying of raw materials, processed secondary materials intended for the production of titanium by melting, machining residues parts of titanium or titanium alloys and other

These secondary materials may have different chemical composition, for example, according to wish the th grade elongated articles but not necessarily. These materials can meet the above alloys.

The availability and cost of secondary elements depends on their mass, that is, the cost of a kilogram of material less than the price of a kilogram of titanium sponge, thus, its use has more advantages.

Mass of titanium or titanium alloy in preparation 10 may also include alloying elements and/or alloy in proportions that depend on the subsequent stage of the method, as used herein, and/or the desired grade of the elongated product.

According to the method according to Fig.1 this is followed by operation of melting by electric arc skull melting method 20 weight titanium or titanium alloy, prepared in the course of the operation 10.

Thus, fusion is carried out in the form of a skull melting.

Skull melting is carried out through a furnace containing a vacuum tank and executed accordingly crucible placed inside the tank.

Set-consumable electrode to the inside of the tank, while the download titanium in the crucible. Generate a large potential difference between the electrode and the crucible. When the potential difference reaches a certain threshold, an electrical arc is formed with a high energy level between the lower end of electrode in the crucible titanium.

In practice, the electrode may be mounted on a vertical portion passing downwards into the tank.

When the electrode is fully melted, the molten mass of titanium, in the crucible, can be transferred at one time, in one or more mold type that you select, in this case with a circular cross section and a diameter of less than 300 mm, placed inside the tank. Thus, the casting is very fast: it can, for example, be performed by tilting the crucible. Skull melting is also a technology of melting/casting by individual parties.

During such melting/casting, part of the molten mass of titanium hardens on the border with crucible and forms a barren rock titanium, protecting titanium smelting from any contamination from other elements present in the crucible or from the crucible. In other words, this waste rock forms an additional crucible located in the crucible, which is provided in the furnace (skull melting). After cooling this waste rock can be used as a consumable electrode for the new smelting, which is of economic interest. The crucible furnace can be designed so that the waste rock has a shape adapted to its further functions consumable electrode.

Prepared by mass of titanium on the stage 10 includes the advantage of the public waste rock or crust, the resulting melting and casting by skull melting method of the initial mass of titanium.

Also, mainly prepared for surgery 10 weight titanium has a high percentage of secondary titanium.

Preferably, the mass of titanium for operation 10 includes only one or a few crusts of recycled material and necessary element alloys or alloying in the appropriate proportions.

In other words, the operation of the preparation of titanium or titanium alloy 10 in this case is mainly the mixture of titanium or titanium alloy, in which most or all of the weight consists of secondary materials. Another may need only the addition of alloying elements.

The method according to Fig.1, therefore, has the advantage mainly in the fact that the method allows to obtain high-quality products, at a lower cost than traditional methods, using almost exclusively of recycled materials with the use of melting by electric arc or skull melting.

The temperature used for the melting operation, called subcooling temperatures may depend on the composition of the mix when the preparation operation 10. Subcooling temperatures above 1600°C allows to melt the mass majority is TBE possible compositions.

According to the method according to Fig.1 then the operation of casting ingots with a mainly circular cross section and a diameter of about 300 mm, Preferably a diameter of these bars should be less than 250 mm, the Casting is carried out using the entire molten mass at a time (one "party" and quickly, for example, by tilting the crucible containing the molten mass of titanium.

There is not a lower limit of the diameter is discharged during the operation of 30 bars. However, for economic reasons it may be preferable to pour ingots with a diameter of 100 mm

Theoretically there is no restriction on the length of the cast on the stage 30 bars.

In practice poured ingots, the length of which corresponds with the length of the bars for drawing during operation 40. For example, the length of the pour during the operation 30 of the ingot can be selected multiple of the length of the ingot for drawing during operation 40, to avoid loss of material. Often the length of the pour during the operation 30 of the ingot may be selected equal to the sum of the lengths of the bars for drawing the lugs 40.

Preferably, during operation of the casting 30 is poured so much of cylindrical ingots as molten during operation 30 weight titanium. Thus, the full benefit because the skull plank which allows casting party. Mass of titanium or titanium alloy, the spitting image during operation 20, and, consequently, the mass of titanium or titanium alloy, prepared in the course of operation 10, can be selected in amounts, based on the number of bars, the drawing which you want to perform, and, therefore, pre-pour, as well as on the basis of their size.

The diameter of each of the cast during the operation of 30 bars is less than 300 mm of Each of these ingots may then be subjected to the drawing operation 40 without substantial reduction of its diameter before the drawing operation.

However, between the casting operation 30 and the drawing operation 40 may be a roughing operation. Despite the fact that during the operation of the roughing certainly there is a reduction of the diameter, this decrease is so small (of the order of several tenths of millimeters) that it cannot be considered as a significant decrease in the diameter of the ingot. In addition, roughing aimed at the removal of the surface layer of the cast ingot, and thus, it cannot be considered a surgical reduction of the diameter, the purpose of which is to substantially reduce the diameter of the ingot.

Cylindrical ingots, cast during the operation, 30 can have the same dimensions in length and diameter. These ingots can also be of a different length and/or diameter, for example, for the manufacture of the population of various elongated products. The diameter and length of each of the cast during the operation, 30 bars can be selected depending on the diameter and length of one or more ingots for drawing during operation 40. You can set the length and diameter of the ingot to lug depending from the elongated product that you want to receive the result of the operation of the lug 40. In other words, the method according to Fig.1 allows to obtain the result of the operation of the casting 30 bar, the size of which is adapted to drawing and dimensions which can be calculated depending on the size of the required extended product.

On this account, the method according to Fig.1 differs from the traditional methods of providing for casting a single ingot, in particular, to reduce the cost per unit mass pour ingot and forging operations to reduce the diameter of the ingot. In other words, the diameter of the poured ingot by traditional methods is limited (on the order of 400-600 mm), whereas in this case, the diameter can be chosen.

It should be noted that, for the limited size of the elongated product in practice there is a range of possible diameters and lengths of the ingot to lug 40. When the elongated articles of different sizes must be obtained by means of the method according to Fig.1, it may be better, if possible, to choose the appropriate size of the diameter of the ingot to voloce the Oia, which could be adapted to the aggregate of such products: thus, you can pour one ingot, which can be cut to obtain ingots, adapted for drawing a variety of elongated products. Thus, the optimized management of available bars for drawing.

It should also be noted that the method according to Fig. 1 allows with the same ease and at a similar cost (plus the price of raw materials) to produce products of larger and smaller diameter. In the classical method, which requires the forging operations to reduce the diameter, on the contrary, more difficult and expensive to make products with a small diameter, which require additional costs for the reduction of diameter, which is most often done by forging.

Currently in the camps do not allow the drawing of bars with a length of 1500 mm. In other words, casted on the stage 30 bars have a length of less than 1500 mm, but can be longer if the displayed mills with great opportunities.

The method according to Fig.1 is completed by operation of the hot lug 40 of cylindrical bars under drawing mill for receiving elongated articles or blanks of this product. The operation of the lug 40 may be adapted to receive solid or hollow products.

The temperature at which lacinia higher than the temperature of the so-called "beta transus", which depends on the composition of the ingot.

The operation of the lug 40 is a hot method at a temperature of, usually part 800°C-1200°C. Preferably, drawing is performed at a temperature above 900°C to ensure good ductility material and lower than 1150°C. in order to avoid unnecessary power consumption, still getting adapted metallographic structure.

The drawing takes place through traditional drawing mill, equipped with Molokai and punch. If you want to make a hollow elongated product is applied more and rod, also referred to as the "needle" (in this case, the ingot for drawing must be pre-made hole).

The drawing is performed in the presence of a lubricating component. This lubricant component usually contains the glass, i.e., the normal lubricating component to the traditional operations of drawing hot way at temperatures above 900°C.

The method according to Fig.1 does not require reduction of the diameter of the ingot poured during the operation 30 before surgery lug 40.

However, it should be understood that this does not exclude that one or more particular operations such as roughing, various kinds of surface processing or cutting, can be performed with the spitting image on the stage 30 ingot to prepare an ingot for drawing to the stage 40.

The metal is formed as an elongated articles obtained during the operation of the lug 40, surprisingly comparable with the metallurgical quality of the products obtained in the traditional way, at least concerning the mechanical strength, in particular measured by a tensile test in a cold way.

This is comparable to the quality obtained in the absence of the forging operation, the predecessor of the lug 40, largely due to the fact that the drawing has a beneficial and sufficient influence on the metallographic structure of small diameter ingots that have been released.

The absence of any transaction by reducing the diameter of the ingot obtained during the operation of casting 30, in particular, the absence of forging, the predecessor of the lug 40, also contributes to reducing the cost of the extended product. The absence of this operation, respectively, and reduces the duration of the manufacture of such products.

No operations of forging, or any other operation for forming the ingot before the drawing operation; and the quality of the elongated product, the resulting drawing, is that, despite the relatively small diameter of the ingots cast in operation 30, the method according to Fig.1 is more economical in relation to the final cost of the extended product than the methods known from the prior art. The duration of manufacture and is available is to be improved in comparison with the known from the prior art.

All cast during the operation, 30 bars, or only some of them can be subjected to drawing in parallel on several different mills, if necessary, after cutting, which especially increases the productivity of the method. In the same way reduces the cost of the extruded product.

Unlike traditional methods, the ingot, the spitting image during the operation, 30, not melted according to the method according to Fig. 1. However, the quality of the elongated articles obtained in the result of the operation lug 40 is entirely sufficient, as for the absence of defects in the casting and mechanical strength, as compared with products obtained after melting "VAR", and without forging operations, a well-known fact that it improves the quality.

Although remelting under vacuum, such as remelting "VAR", is regulated by certain standards for elongated products of high quality (or high strength), the applicant has determined that the products obtained by the method according to Fig.1, also suitable for applications under these standards, despite the absence of such a meltdown.

In Fig.2 shows a variant implementation of the method according to Fig.1.

The operation of casting ingots 30 in this case includes the operation of the first casting of ingots with a diameter of less than 300 mm 300, then "melting VAR" 302 these first bars. In other words, each of the th of the first ingot, obtained after melting/casting method "skull melting, or at least some of them, separately subjected to melting "VAR". These first bars are consumable electrodes for such melting.

The operation of casting ingots 30 then includes the steps of casting ingots for drawing from the second mass of molten material, i.e., ingots of cylindrical shape and of a diameter less than 300 mm

When melted down "VAR", casting is performed in stages, as the consumable electrode is melted. The diameter of the resulting strand or the second strand are usually higher by 10-20% than the diameter of the electrode. Therefore, the diameter of the cast during the operation 300 ingots should be given this increase, in part because the bars for drawing at operation 40, typically have a diameter of less than 300 mm without any need to perform an operation to reduce the diameter.

In Fig.3 shows the end-to-end processing 50 or intermediate processing, which may be elongated articles obtained in accordance with one of the methods shown in Fig.1 and 2.

Elongated product, which is obtained during the operation of the lug 40 may be one or more of the following operations:

one or more heat treatments (in the oven) and one or more chemical (e.g., cleaning) or physical education is Otok surface 51;

- straightening operation and unwinding 52 intended for straightening elongated workpieces, in respect of their cross-section and of the General form;

- the operation of thermal processing 53;

- the operation to give the desired length 54 by means of sawing or cutting,

- the operation of sandblasting 55, also known as blasting sand;

the operation for forming 56,

the operation control 57 by means of one or several known control technologies without destroying the product, such as ultrasound, x-ray, eddy currents and other,

- mechanical processing.

These operations are presented solely for illustrative manner and equally can be performed in a different order.

The proposed method allows to obtain extra long products of satisfactory quality, relative to existing standards, without forging operations, which makes optional the traditional smelting operation "VAR" and provides a significant opportunity to use recycled material.

The proposed method eliminates the forging operation. In the end, the applicants have proved, against all expectations and against widely used in engineering ideas that are comparable or at least sufficient mechanical properties elongated products can be obtained only through drawing, making excessive beneficial de is due to the forging operation.

The presented method has a lower production cost, reduced manufacturing time and greater availability of products.

The present invention is not limited by the methods described above are intended only as examples. In particular:

Operation 20 melting and casting 30 is described as performing skull melting. This melting technique allows melting/casting lots, in contrast to the piecemeal methods of melting/casting. Today only, this technology allows this method of casting. However, the methods according to Fig.1 and 2 can be performed by other smelting technology, if only she had characteristics similar to skull melting, then there are ways possible to produce ingots suitable for drawing, with a diameter of less than 300 mm, with a reasonable price, preferably with the use of a large number of secondary material and casting party.

- Turning on the stages 302 and 304 may be implemented in various ways melting, if only they improved metallurgical quality of the resulting ingots and allowed, with acceptable cost, to obtain ingots adapted for the operation of the lug 40 size, i.e. with a diameter of less than 300 mm

Upon completion of the lug 40 or, if necessary, the operation end processing 50, obtained odlin the TES product may be subjected to one or more operations for forming, in particular forging, including those designed to further reduce its cross section.

- Can be seen in the broader plan drawing of ingots with a diameter of less than 300 mm directly after they have been melted down "VAR", without reducing the diameter of the pre-forging, despite the fact that the first melting/casting was performed according to any method which would allow us to pour ingots adapted diameter at a reasonable price.

- Received elongated articles may be subject to a subsequent molding, for example, bending.

The present invention has been described with reference to the field of aviation, in particular about working in this field standards. This is because the industry is a vast scope of elongated products of titanium and requires high quality of these products. This does not limit the application of the described method in this specific industry. However, other industries that use extra long products made of titanium or titanium alloy and requires high-quality products, can refer to the standards for the aviation industry, while not being a part of this industry. The present invention is applied in such industries. In General, the invention is directed for use in the SEH, in addition to aviation industries, which require extra long high quality products of titanium in the sphere of aviation. On this account the method according to the invention offers such flexibility and the cost reduction that can be implemented elongated articles of titanium in areas not associated with aircraft and/or for General use.

Strictly speaking, the elongated products made according to the method according to Fig.1, do not meet the U.S. standard AMS 4935 for use in aircraft because it does not pass through several heats, including vacuum. But, nevertheless, they are products of comparable quality, in particular its mechanical strength. The applicant believes that these products can be used instead of the products identified by this standard, or the standard should be modified to include products obtained by the method according to Fig.1. In any case, the quality of these products is such that in many industries, which uses this standard, but is not strictly limiting, you can safely use them.

The present invention encompasses all variants that can predict the specialist in the art in light of the present description.

1. Method for the production of long products and billets of titanium or a titanium alloy, comprising the taps:
a) preparing a mass of titanium or titanium alloy (10) to heat,
b) skull melting specified weights by means of an electric arc (20),
c) casting from a molten mass of one or more ingots mainly cylindrical shape with a diameter of less than approximately 300 mm (30), then
d) drawing one or more of these ingots at a temperature between 800°C-1200°C by drawing mill (40).

2. The method according to p. 1, characterized in that step C) comprises the following steps:
C1) casting one or more first ingots from molten mass (300),
C2) smelting of each of these first ingot to obtain a second corresponding mass of titanium or titanium alloy (302),
C3) the casting of one or more ingots for drawing, mainly cylindrical shape with a diameter of less than approximately 300 mm from each of the specified second corresponding mass of titanium or titanium alloy (304).

3. The method according to p. 2, wherein step 1) comprises the steps:
C11) casting one or more ingots mainly cylindrical shape with a diameter of less than approximately 300 mm from the molten mass (300).

4. The method according to p. 3, characterized in that the step C3) comprises the step:
A31) the casting of the ingot for drawing mainly cylindrical shape with a diameter of less than approximately 300 mm from each of the specified second corresponding mA is with titanium or titanium alloy.

5. The method according to p. 4, wherein step C2) comprises the steps:
C21) melting at least a first ingot by vacuum arc.

6. The method according to p. 1, characterized in that the cast ingot for drawing diameter less than 250 mm

7. The method according to p. 1, characterized in that the cast ingot for drawing with a diameter of 100 mm

8. The method according to p. 1, characterized in that in step d) the drawing shall be implemented by drawing mill using a lubricating component.

9. The method according to p. 8, wherein the drawing is performed with the use of lubricating component containing the glass.

10. The method according to p. 1, wherein the drawing is carried out at a temperature of 900°C.-1150°C.

11. The method according to p. 1, wherein step C) includes:
C1) casting practically the whole mass of titanium or titanium alloy, the molten skull melting method by means of an electric arc at the stage b) into ingots for drawing mainly cylindrical shape with a diameter less than 300 mm

12. The method according to p. 1, characterized in that before drawing carry out the Stripping of the ingot.

13. The method according to any of paragraphs.1-12, characterized in that before drawing the cast ingot on the stage) in diameter depending on the diameter of the elongated product.



 

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EFFECT: after straightening the stock material conserves high durability characteristics.

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9 cl, 2 tbl

FIELD: process engineering.

SUBSTANCE: invention relates to metal forming and can be used for production of articles from three-component titanium-based alloy containing 2-6 wt % of aluminium and not over 4 wt % of vanadium or zirconium. Billets are subjected to equal-channel angular pressing at 400-470°C at the rate of 0.1-1.0 mm/s. Note here that nano- and sub microcrystalline structures are formed in the billet with grain size not over 0.5 mcm. Deformed billets are subjected to isothermal annealing at 450-550°C for 0.5-1.0 h. Then, the billet is subjected to upsetting or rotary forging at the temperature not higher than that of isothermal annealing.

EFFECT: higher strength and operating performances.

3 cl, 1 dwg

FIELD: process engineering.

SUBSTANCE: invention relates to metal forming and is intended for straightening of rolled sheet in annealing at constant load, primarily, large-size sheets and boards from titanium alloys. Proposed creep annealing comprises setting of batch composed of one or several sheets onto steel heated plate of vacuum straightening plant. Plant inner space is evacuated at simultaneous loading of the batch outer side, heating to annealing temperature is performed as well as holding and cooling. Cooling is executed with intermediate stage at temperature of 220±20°C with holding of 1 to 5 hours.

EFFECT: stable sheet surface shape.

2 cl

FIELD: metallurgy.

SUBSTANCE: equichannel angular pressing of a cylindrical workpiece is performed. Ultra-fine structure with the grain size of 200-300 mcm is formed in the workpiece metal. Then the workpiece is cut into disks with each of them being subject to intensive plastic deformation by torsion with the help of two rotating strikers. Deformation of torsion is carried out under the room temperature and the pressure of 4-6 GPa with the number of strikers' revolutions n≤2. Therewith the homogeneous nanocrystalline structure with the grain size of ≤100 mcm is formed.

EFFECT: improved physical and mechanical properties of the material being processed.

2 cl, 1 tbl, 1 ex

FIELD: metallurgy.

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.

1 ex

FIELD: medicine.

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: metallurgy.

SUBSTANCE: manufacturing method of thin sheets from pseudo-alpha titanium alloys involves deformation of an ingot into a slab, mechanical processing of a slab, multipass rolling of a slab for a semi-finished rolled stock, cutting of the semi-finished rolled stock into sheet workpieces, their assembly into a pack and its rolling and finishing operations. Multipass slab rolling is performed at several stages. After the semi-finished rolled stock is cut into sheet workpieces, their finishing operations are performed. Assembly of sheet workpieces into a pack is performed by laying so that direction of sheets of the previous rolling is perpendicular to direction of sheets of the next rolling. Rolling of the pack is performed till a final size, and then, obtained sheets are removed from it and finishing operations are performed.

EFFECT: obtaining a microstructure of sheets, which provides high and uniform level of strength and plastic properties.

1 dwg, 2 tbl

FIELD: metallurgy.

SUBSTANCE: ingot is subjected to swaging-drawing to octahedron with total reduction of 1.6-1.7. Final forming is performed at shaped hammers at 4-5 displacements over hammer surface and, then, in closed sizing die. Total reduction ay final forming makes 3-5.

EFFECT: precise forged pieces with homogeneous fine-gram structure, high specific strength and ductility.

2 cl, 2 tbl, 1 ex

FIELD: metallurgy.

SUBSTANCE: proposed alloy features density at a room temperature of not over 4.2 g/cm3, solidus temperature of at least 1450°C, the number of phases α2 and γ at 600-800°C making at least 20 wt % and at least 69 wt %, respectively. Total quantity of said phase makes at least 95 wt % while niobium content in γ-phase makes at least 3 wt %. Proposed method consists in that said γ-TiAl alloy containing niobium in amount of 1.3 or 1.5 at. % and transition metals selected from chromium in amount of 1.3 or 1.7 at. % and zirconium in amount of 1.0 at. % is subjected to hot isostatic forming. Said forming is combined with annealing at 800°C and holding for 100 hours.

EFFECT: low density, stable phase composition at operating temperatures.

2 cl, 2 dwg, 4 tbl, 1 ex

FIELD: metallurgy.

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.

1 tbl

FIELD: metallurgy.

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.

1 ex

FIELD: medicine.

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: metallurgy.

SUBSTANCE: proposed process comprises production of the mix of powders, forming the pellet therefrom and execution of self-propagating high-temperature synthesis. Obtained the mix of pure metals containing titanium, aluminium, niobium and molybdenum in the following amount, it wt %: aluminium - 40-44, niobium - 3-5, molybdenum - 0.6-1.4, titanium making the rest. This pellet is compacted to relative density of 50-85% and subjected to thermal vacuum processing at 550-560°C for 10-40 min, heating rate of 5-40°C/ min and pressure of 10-1-10-3 Pa while SPS is performed at initial temperature of 560-650°C.

EFFECT: preset shape of casts, high mechanical properties.

2 dwg, 2 tbl, 2 ex

FIELD: metallurgy.

SUBSTANCE: proposed alloy features density at a room temperature of not over 4.2 g/cm3, solidus temperature of at least 1450°C, the number of phases α2 and γ at 600-800°C making at least 20 wt % and at least 69 wt %, respectively. Total quantity of said phase makes at least 95 wt % while niobium content in γ-phase makes at least 3 wt %. Proposed method consists in that said γ-TiAl alloy containing niobium in amount of 1.3 or 1.5 at. % and transition metals selected from chromium in amount of 1.3 or 1.7 at. % and zirconium in amount of 1.0 at. % is subjected to hot isostatic forming. Said forming is combined with annealing at 800°C and holding for 100 hours.

EFFECT: low density, stable phase composition at operating temperatures.

2 cl, 2 dwg, 4 tbl, 1 ex

FIELD: metallurgy.

SUBSTANCE: proposed alloy comprises the following elements, in wt %: carbon - 0.03-0.10; iron - 0.15-0.25; silicon - 0.05-0.12; nitrogen - 0.01-0.04; aluminium - 1.8-2.5; zirconium - 2.0-3.0; samarium - 0.5-5.0, titanium and impurities making the rest.

EFFECT: higher efficiency of absorption, better working and bonding properties.

3 tbl, 1 ex

FIELD: metallurgy.

SUBSTANCE: solder contains components at the following ratio in wt %: zirconium - 45-50, beryllium - 2.5-4.5, aluminium - 0.5-1.5, titanium making the rest. Solder represents a flexible band and is produced by super-rapid tempering of the alloy by casting the melt of revolving disc.

EFFECT: higher operating performances, decreased intermetallide interlayers in the weld.

3 cl, 11 dwg, 1 ex

FIELD: metallurgy.

SUBSTANCE: production of titanium-based allot with content of boron of 0.002-0.008 wt % comprises smelting in vacuum arc skull furnace with consumable electrode without extra vacuum port for addition of modifying additives. Preform of modifier B4C wrapped in aluminium foil is fitted in consumable electrode bore drilled from alloyable end to distance defined by electrode fusing interval.

EFFECT: titanium-based alloy of equiaxed structure and grain size smaller than 15 mcm.

1 tbl, 1 ex

FIELD: metallurgy.

SUBSTANCE: titanium-based alloy contains the following, wt %: Al 5.0-6.6, Mo 1.5-2.5, Zr 1.0-2.8, V 0.4-1.4, Fe 0.08-0.40, Si 0.08-0.28, Sn 1.5-3.8, Nb 0.4-1.2, O 0.02-0.18, C 0.008-0.080, Ti is the rest.

EFFECT: alloy has high strength characteristics at high temperatures, increased processibility level at hot deformation.

2 cl, 3 tbl, 3 ex

FIELD: process engineering.

SUBSTANCE: invention relates to powder metallurgy. It can be used in production of pyrotechnic fuses, as gas absorbers in vacuum tubes, lamps, vacuum hardware and gas cleaners. Oxide of basic element selected from Ni, Zr and Hf is mixed with alloying metal powder selected from Ni, Cu, Ta, W, Re, Os or Ir and with reducing agent powder. Produced mix is heated in kiln in atmosphere of argon to initiation of reduction reaction. Reaction product is leached, flushed and dried. Said oxide of basic element features mean particle size of 0.5-20 mcm, BET specific surface of 0.5-20 m2/g and minimum content of said oxide of 94 wt %.

EFFECT: powder with reproducible combustion time, specific surface and distribution of articles in sizes and time.

23 cl, 5 ex

FIELD: process engineering.

SUBSTANCE: proposed method aims at increasing wear resistance of rolls and process efficiency and decreasing wastes at rolling. It comprises making an intermediate blank and its rolling at rolling plant at feed of its front end to rolling unit at initial moment of rolling. Note here that before said feed, this intermediate blank is formed by squeezing its front end at four-hammer press forge to produce conical part with taper angle not larger than friction angle at sections of contact of intermediate blank front end with rolling mill rolls. Note also that reduction of hammers is performed with formation of concave surfaces at front end angles with the help of four hammers appropriately shaped.

EFFECT: perfected rolling process.

4 cl, 8 dwg

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