Method of fabrication of thin sheets from two-phase titanium alloy and product from these sheets

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy, in particular to the method of fabrication of thin sheets from two-phase titanium alloy with microcrystalline structure which, in particular, is suitable for superplastic heat deformation. The method includes furnace charge preparation, ingot smelting, ingot deformation in a slab in three stages, slab machining, slab rolling for semifinished rolled products, cutting of semifinished rolled products into work pieces, rolling of work pieces into sheets, heat treatment and moulding. The titanium alloy ingot is melted which contains wt %: 3.5-6.5 Al, 4.0-5.5 V, 0.05-1.0 Mo, 0.5-1.5 Fe, 0.10-0.2 O, 0.01-0.03 C, 0.005-0.07 Cr, 0.01-0.5 Zr, 0.001-0.02 N, the rest is titanium, with the strength of aluminium [ A l ] e q s t r = 6 , 0 1 1 , 5 5 and molybdenic [ M o ] e q s t r = 3 , 5 5 , 6 equivalents.

EFFECT: obtaining of high-strength sheet products with the thickness < 3 mm with high plastic properties at the room temperature and suitable for SPD when heating.

5 cl, 4 dwg, 3 tbl

 

The invention relates to the field of metal forming, and more particularly to rolling production, and relates to a method of manufacturing a highly economically advantageous prefabricated sheet of two-phase titanium alloy with microcrystalline structure, which, in particular, suitable for superplastic deformation (SPD) during heating.

The trend to reduce the cost of titanium semi-finished products and increase their operational and technological properties has always been decisive. One of the most important properties of sheet semi-finished products is plasticity - the ability under the action of external mechanical stresses to change shape without breaking. This property is widely used in technology in the manufacture of products from sheet semi-finished products (flexible, fume hood, etc.). Relatively recently opened, the effect of superplasticity (SP) - state material having a crystalline structure, which allows the deformation of an order of magnitude greater than the maximum possible for this material in the normal state, allows with minimal cost of manufacturing products with complex geometric shapes.

The conditions of transition to SP-as determined by three main factors (Kaibyshev O. A. Superplasticity of industrial alloys. M, metallurgy, 1984, p. 10):

-the presence ultrarelativistic (UMP) structure (grain size < 10-15 μm);

the deformation temperature (TD) greater than 0.4 of the melting temperature (TPL);

- the rate of deformation.

You should also consider the chemical composition of the titanium alloys because the selection of materials for specific products is made, as a rule, subject to the performance requirements of the material and not of adaptability, although the latter factor is also taken into account. So to each specific material being sought pre-processing, providing the production of small grains. When processing also takes into account economic requirements, requirements for surface condition, the accuracy of the geometrical sizes and shapes, mechanical properties, due to the structure and the anisotropy or isotropy of mechanical properties depends on the type formed by rolling metallographic texture.

A method for manufacturing a wafer-thin sheets of high-strength titanium alloys, including the production of the original slab, the Assembly of the package of sheet blanks daubed with a coating with the use of a case, hot rolling and heat treatment package, split and trim sheets obtained (Patent RF №2381297, publ. 10.02.2010). Sheets made according to the method, have low properties of superplastic and is not suitable for sheet molding �condition of superplasticity.

A method for manufacturing thin sheets of high-strength titanium alloys, including operations training billets and hot deformation of package blanks in the shell. The original billet with grain size of the alpha phase is not more than 2 μm is obtained by hot rolling forged or extruded slab with a relative thickness of h3(α+β)hk=8,0-10,0, where h3- the thickness of the initial preform batch before rolling, mm, hk- the ultimate thickness of the finished sheet, mm. Then the workpiece is cooled at a speed of 200-400°C(α+β)min, and subsequent thermomechanical processing of the package is carried out in quasi-isothermal conditions by means of hot rolling of the package blanks are placed in the steel case, the longitudinal and transverse directions with a turn of 90°, with the direction of rolling is carried out at a total degree of deformation in one direction 60-70% (patent RF №2250806, publ. 27.04.2005) - prototype.

The disadvantage of the prototype is that the method is not regulated chemical composition of the treated alloys, which largely determines the level of mechanical properties at room temperature, in particular the parameters of plasticity, elongation characteristics and angle of bend. The manufacturing processes are of a General nature and is not optimized for �of Holocene from a specific alloy economically of sheet metal, suitable for superplastic deformation (SPD) during heating and high plastic properties at room temperature.

Task to be solved by the present invention is to obtain rolled products, with high technological and operational properties of economically titanium alloy.

The technical result achieved by carrying out the invention, is to obtain high-strength rolled sheet of a thickness of < 3 mm with high plastic properties at room temperature and suitable for SPD during heating, and reducing the cost of products is achieved thanks to the possibility of engaging in scrap waste materials titanium alloys.

The technical result is achieved in that in the method of manufacturing thin sheets of two-phase titanium alloy, including the preparation of the charge, ingot smelting, deformation of the ingot into a slab, machining of the slab, rolling the slab at tackle, cutting rolled into billets, rolling of billets into sheets, heat treatment and forming, for the manufacture of sheets used titanium alloy containing (wt.%) 3,5-6,5 Al, 4.0 to 5.5 V, 0.05 to 1.0 Mo, 0.5 to 1.5 Fe, 0,10-0,2 O, 0.01 To 0.03 s, From 0.005 To 0.07 Cr, and 0.01 to 0.5 Zr of 0.001-0.02 N, the rest is titanium, with quantities strength aluminumand molybdenum equivalents constitutingdefined by the formulas:

the ingot formed in the slab in three stages: at first, after heating to a temperature of 200÷280°C higher than the temperature of polymorphic transformation (CCI) with a total degree of deformation of 30÷70%; on the second heating at 150÷200°C above the CCI with a total degree of deformation of 40÷80%; the third heating to a temperature of 20÷80°C below CCI, the rolling of the slab at tackle is produced in four stages: at first, after heating to a temperature of 100÷150°C above the CCI rolling in the longitudinal direction with a total degree of deformation of 50÷95%; after the second heating to a temperature of 20÷100°C below the CCI in the longitudinal direction with a total degree of deformation of 10÷25%; the third, after heating to a temperature of 20÷100°C below the CCI in the transverse direction at a total degree of deformation of 20% to 35%; on the fourth after heating to a temperature of 20÷100°C below the CCI in the transverse direction at one or more stages of deformation in a single step 20-35%, with total degree of deformation of 30-50%, then the cutting of the rolled sheet on the workpiece and finishing operations, rolling of billets into sheets is carried out by an Assembly of plates in a bag and rolling on the finished package size in the longitudinal direction produced in St�linen case with heating to a temperature of 40÷150°C below the CCI with the degree of deformation of the package for the pass 10÷20% with the total deformation of the package 50÷80% with subsequent annealing in the composition of the case at a temperature of 650-900°C for 40-80 minutes, and then finishing processing obtained after disassembly of packets of sheets.

Reducing the cost of manufacturing of sheet semi-finished product, and therefore of the products is achieved by the inclusion in the charge to 40% titanium waste.

The forming of the sheet can be performed by superplastic forming at a temperature of 750-800°C from the leaves and strain rate of 3.5×10-4h-1-4,5×1-4h-1.

The forming of the sheet can be performed at room temperature.

A thin sheet of two-phase titanium alloy with high plastic properties at room temperature and suitable for SPD when heated, can be manufactured by this method.

The invention is based on the possibility of making thin sheets with high plastic properties.

The chemical composition of the alloy is selected taking into account the possibilities of the presence of alloying elements in titanium waste.

The group of α-stabilizers

Aluminum, which is used in almost all industrial alloys, is the most effective reinforcer, improving strength and heat resistant properties of titanium. The content of aluminum�I in the alloy taken from 3.5 to 6.5%, when the aluminum content is more than 6.5% is undesirable reduction of plasticity.

Nitrogen, oxygen and carbon raise the temperature allotropical turning titanium and mostly present in industrial titanium alloys in the form of impurities. The impact of these impurities on the properties of manufactured of titanium alloys is of such significance that should specifically be taken into account in the calculation of the charge to obtain the mechanical properties in the desired range. The presence in the alloy of nitrogen in the range of 0,001-0,02%, oxygen 0,10-0,2%, carbon 0,01-0,03% has no significant impact on the reduction of ductility at room temperature.

The group of neutral reinforcers

Recently as alloying elements used zirconium. Zirconium reacts with α-titanium with a wide range of solid solutions, relatively close to the melting point and density, improves corrosion resistance. Microalloying with zirconium in the range of 0.01 to 0.5% provides a combination of high strength and plasticity.

The group of β-stabilizers, which are widely used in industrial alloys (V, Mo, Cr, Fe)

Vanadium and iron are β-stabilizing elements that increase the strength of the alloy. When the vanadium content of more than 5.5% is undesirable reduction of plasticity.

At an iron content of less than 0.5% to ensure sufficient� effect and when the content of more than 1.5% is undesirable reduction in the ductility of the alloy at room temperature.

In the inventive alloy in a small amount is present β-stabilizing element is chromium, which is also aimed at increasing the strength of the alloy. The chromium content in the range from 0.005 to 0.07% slightly increases strength properties and increases the ductility, since chrome has the titanium lower coefficient of diffusion mobility than other β-stabilisator (Kaibyshev O. A. Superplasticity of industrial alloys. M, metallurgy, 1984, p. 211), however its presence in the alloy allows the use of titanium waste containing this element.

The introduction of molybdenum in the range of 0.05 to 1.0% provides complete solubility in α-phase, which allows to obtain the necessary strength characteristics without reducing plastic properties. If the molybdenum content exceeds 1.0%, there is a decrease in the plastic properties of the alloy, however, its presence in the alloy allows the use of titanium waste containing this element.

The ratio of chemical elements is regulated by the introduction of strength aluminumand molybdenumequivalents, these values are integrated, which allows to obtain alloys with predicted structural and IU�adicheskii properties. Border equivalentsanddetermined empirically and can guarantee an optimal combination of structural and technological properties of the alloy.

Thermomechanical processing is carried out in the following order.

Free forging of the ingot at a temperature of β-region with a degree of 30÷70% after heating to a temperature of 220÷280°C higher than the temperature of polymorphic transformation (CCI) cast structure destroys and crushes primary β grain.

Next produce free forging of the billet with the degree of 40-80% after heating to a temperature of 150÷220°C above the TPP. The heating temperature of the workpiece and the degree of deformation is determined based on the conditions of obtaining a regulated structure in end products.

On the first and second stages of forging be brewed differently oriented shell and the metal seal at the junction of dendrites, mechanical homogenization of the alloy, and the removal of zonal and dendrite segregation in the ingot.

Forging the billet into a slab in the (α+β)-region after heating for 20÷80°C below the temperature of polymorphic transformation, the so-called "semihot hardening" destroys the high angle grain boundaries. The degree of deformation of 30÷40% identified the need to obtain sufficient metal energy, contributing to the process recrystallization�Oh processing during subsequent heating of the slab to temperature β-region.

After forging operations, the slab is mechanically treated to remove forging surface defects and gas-saturated layer.

Further machined slab is rolled at tackle in four stages.

In the first stage, after heating is to a temperature of 100÷150°C above the CCI rolling in the longitudinal direction with a total degree of deformation of 50÷95%. During heating of the slab for rolling to a temperature of 100÷150°C higher than the temperature of polymorphic transformation happen recrystallization of β-phase grain refinement and the formation of a macrostructure. Heating the slab to a temperature below the specified temperature range causes the streaky structures and the decrease of plastic properties of the alloy. Heating to temperatures above the specified range causes a collective recrystallization of the alloy and leads to the formation of large grains, and initiates cracks in the formation of a large gas-saturated layer on the surface of the rolled sheet. The degree of deformation of 50+95% due to the provision of necessary deformation of slabs in the (α+β)-region during subsequent rolling. After rolling with the purpose of fixing the recrystallized β-phase followed by cooling the roll to room temperature.

In the second stage in the deformation process of roll in (α+β)-region is the formation of the microstructure. P�more okatku lead after heating to a temperature of 20÷100°C below the CCI in the longitudinal direction with a total strain of 10÷25%. Heating of the above peal (CCI-20)°C leads to the coarsening of the structure with possible overheating of the metal and, as a consequence, the mismatch of mechanical properties and structure of finished products. Heating of the transfer bar below (CCI-100)°C is the freezing of the metal and leads to the appearance of surface cracks of roll due to the lower ductility of the metal. Rolling in the (α+β)-region with the degree of deformation less than 10% reduces the efficiency of the process in connection with a small amount of deformation, increasing the number of heating and deforming operations. Rolling in the (α+β)-region with the degree of deformation of more than 25% increases the duration of the process, thereby causing a significant effort due to the cooling of the rolled metal. After rolling in (α+β)-region with the aim of obtaining a homogeneous microstructure was followed by cooling of the received burst to room temperature.

In the third stage rolling is carried out after heating to a temperature of 20÷100°C below the CCI in the transverse direction with a total degree of deformation of 20-35%, transverse rolling helps to reduce the anisotropy of mechanical properties.

In the fourth stage rolling is carried out in the transverse direction after heating to a temperature of 20÷100°C below the CCI in the longitudinal direction in one or more stages of deformation in a single step 20-35%, with a total extent of deform�tion 30-50%. The number of stages depends on the required thickness of the rolled before a batch rolling.

Rolling in the (α+β)-region with deformation rate of 20-35% in one step is performed in order to obtain highly dispersed globular-lamellar vnutrikabinnoe (α+β)-structure. Heating of the above peal (CCI-20)°C leads to the coarsening of the structure with possible overheating of the metal and, as a consequence, the mismatch of mechanical properties and structure of finished products. Heating of the transfer bar below (CCI-100)°C is the freezing of the metal and leads to the appearance of surface cracks of roll due to the lower ductility of the metal. Rolling in the (α+β)-region with the degree of deformation less than 20% reduces the efficiency of the process in connection with a small amount of deformation, increasing the number of heating and deforming operations. Rolling in the (α+β)-region with the degree of deformation of more than 35% contributes to the formation of unfavorable textures that influence plastic properties at room temperature, in particular reducing the bending angle of sheet semi-finished product.

Then the cutting of the rolled sheet on the workpiece and adjusting operations for the preparation of preforms for batch rolling.

Further grain refinement mode is provided by thermo-mechanical deformation of the package blanks in the longitudinal direction, about�sodimas in the shell (steel case). Hot rolling at a temperature TPP - (40-150°C with deformation 50-80% promotes the formation of fine globular α-phase.

Crystallographic texture of the sheets to form a longitudinal rolling direction of the package, which allows to obtain the crystallographic texture of the base type and to reduce the anisotropy of mechanical properties.

The amount of deformation of the package for the pass 10÷20% is chosen empirically from the condition to the full elaboration of the cross section of the workpiece.

The annealing is performed in the composition of the case at a temperature of 650-900°C for 40-80 minutes.

Agustina processing of the finished sheets produced in a known manner.

Products from the resulting sheets are produced by a method of superplastic deformation under the following process conditions:

strain temperature of 750-800°C;

- strain rate of 3.5×10-4h-1-4,5×10-4h-1.

For LDS is characterized by a sharp dependence of mechanical properties on temperature of deformation, in particular one of the main conditions for obtaining the best values of superplastic in two-phase titanium alloy is to establish approximately equal to the number of phases (50% α-phase and 50% β-phase), which occurs after heating the metal more than 750°C. increasing the temperature above 800°C causes significant grain growth, which leads to a reduction�Oia JV.

The optimum strain rate of 3.5×10-4h-1-4,5×10-4h-1determined empirically.

The ductility at room temperature is guaranteed obtained fine globular structure, and an optimal set of alloying elements in the alloy in which the content of β-phase at this temperature is about 14%.

Industrial applicability of the invention is confirmed by specific examples of its implementation.

To obtain a sheet thickness of 1.0 mm were melted ingots of two-phase titanium alloy with a diameter of 650 mm and a weight of 1800 kg. Chemical composition of the alloy is given in tab. 1. The temperature of polymorphic transformation of the alloy 940°C.

The ingot was subjected to forging by flattening in a taper in the thickness of 250 mm after heating to 1190°C (200°C higher CCI) with deformation rate of 53%. Then the billet was heated to a temperature of 1100°C (160°C above CCI) and was carried out by forging a billet of rectangular cross section. In the third stage, the billet was heated to a temperature of 900°C (40°C below CCI) and forged in the slab dimensions 208×820×2170 mm with a total degree of deformation of 30%. Next, the forged slab struck on the dimensions 194×805×2170 mm. Slab heated to the setting temperature of 1080°C (140°C above CCI) and rolled in several passes to a thickness of 15 mm with total�Epen deformation stage was 92.4%. Next, the substrate was heated to a temperature of 900°C (40°C below CCI) and was produced by rolling in two passes to a thickness of 12.5 mm with a total strain of 15%. Further rolling was carried out at a temperature of 900°C (40°C below CCI) in the transverse direction at a thickness of 4.5 mm. Rolling was carried out for several heatings with degrees of deformation in each of 20...30%. The total degree of deformation was 65%. Then rolled cut-to-length blanks, carried out finishing operations and collecting the bags, while the blanks were placed in the package so that the direction of the subsequent rolling was perpendicular to the direction of the previous rolling. In the package is stacked by three blanks, taking into account the upper and lower steel plates of the thickness of the package amounted to 50.9 mm. Then carried out the final stage of rolling a batch method, for which the packages were heated to a temperature of 850°C (90°C below CCI) and rolled in two passes to a thickness of 38.5 mm (degree of deformation of 16% and 10%) on passes). Then was carried out by heating and rolling in two passes for a thickness of 29 mm package (the degree of deformation of the passages 16% and 10%, the total degree of deformation of 24.7%), after which the produced heating and rolling of the package in two passes for a thickness of 22 mm package (the degree of deformation of the passages 16% and 10%, the total degree of deformation of 24.0%), next was carried out by heating and �rogatko in two passes for a thickness of 16 mm package (the degree of deformation of the passages 16% and 13%, the total deformation of 27.2%). The total degree of deformation of the package amounted to 65%. Then we proceeded with disassembly of packets, resulting in the sheets the size of 1.35×1130×2650 mm.

The obtained sheets were produced by adjusting the processing, cutting to finished size, sampling and testing of mechanical properties and structure research. The results of testing the mechanical properties of sheets of thickness 1 mm in the delivery state and after heat treatment conducted on the samples are summarised in table. 2, images of the microstructure of the sheets shown in Fig. 1 - typical microstructure of sheets of 1.0 mm thickness, alloy VST2k, in the state of delivery (×100) of Fig. 2 - typical microstructure of sheets of 1.0 mm thickness, alloy VST2k, in the state of delivery (×500), the grain size of the α-phase 4 μm, the amount of primary α-phase 65%, degree of globularization 80%. Fig. 3 shows a photograph of the specimen formed by the SPD method, which shows the measuring points 1 and 2, the results of the tests on the properties of superplastic shown in the diagram. Fig. 4 is diagram of the dependence of the true stress-true strain based on the results of tests of tensile specimens from sheets of the alloy VST2K at a temperature of 775°C and a constant strain rate of 3×10-4h-1. The surface quality of the sheets match the requirements of the standard�Oh documentation cracks and delaminations is not fixed.

From the resulting sheets (thickness of sheet 1.0 mm) by the method of the SAP were made two experimental details the details shown in Fig. 3. The results of experimental work are shown in table 3.

Surface quality comparable with standard parts after SPF alloy Ti6A14V SPF.

At room temperature the obtained sheets with thickness of 1.0 mm was investigated the bending angle along and across the direction of rolling. The bend angle up to 180°. In the process of bending the occurrence of cracks was not observed.

Thus, the present invention in comparison with known methods, makes it possible to obtain an economical two-phase titanium alloys thin sheets having satisfactory surface quality, high mechanical properties with minimal anisotropy and a homogeneous structure that has the properties of superplasticity at temperatures of 750...800°C, also on pre-production sample confirmed plastic properties allowing production of sheet punching, bending and method of the SAP products with complex geometric shapes.

1. Method of making thin sheets of two-phase titanium alloy, including the preparation of the charge, ingot smelting, deformation of the ingot into a slab, the line�th processing slab, rolling of the slab at tackle, cutting rolled into billets, rolling of billets into sheets, heat treatment and molding, characterized in that the smelted ingot of titanium alloy containing, wt.%: 3,5-6,5 Al, 4.0 to 5.5 V, 0.05 to 1.0 Mo, 0.5 to 1.5 Fe, 0,10-0,2 O, 0.01 to 0.03 C, 0,005-0,07 Cr, and 0.01 to 0.5 Zr of 0.001-0.02 N, the rest is titanium, with quantities strength aluminum[Al]eKinppand molybdenum[Mo]eKinppequivalents the components of[Al]eKinpp=6,011,55;[Mo]eKinpp=3,55,6and defined by the formulas:
[Al] eKinpp=%aAl+%aZr/3+20[%aO]+33[%aN]+12[%aC]wt.%,
[Mo]eKinpp=%aMo+%aV/1,7+%aNi+%aCr/0,8+%aFe/0,7wt.%,
the ingot formed in the slab in three stages: at first - after heating to a temperature of 200÷280°C higher than the temperature of polymorphic transformation (CCI) with a total degree of deformation of 30÷70%, the second - after heating at 150÷200°C above the CCI with a total degree of deformation of 40÷80%, and the third is after heating to a temperature of 20÷80°C below CCI, the rolling of the slab at tackle is carried out in four stages: at first - after heating to a temperature of 100÷150°C above the CCI in the longitudinal direction with a total degree of deformation of 50÷95%, the second - after heating to a temperature of 20÷100°C below the CCI in PR�longitudinally direction with a total degree of deformation of 10÷25%, the third is after heating to a temperature of 20÷100°C below the CCI in the transverse direction at a total degree of deformation of 20-35% at the fourth - after heating to a temperature of 20÷100°C below the CCI in the transverse direction at one or more stages of deformation in a single step 20-35% and the total degree of deformation of 30-50%, then the cutting of the rolled sheet on the workpiece and finishing operations, rolling of billets into sheets is carried out by an Assembly of plates in a bag and rolling on the finished package size in the longitudinal direction is produced in steel case with heating to a temperature of 40÷150°C below the CCI with the degree of deformation of the package for the pass 10÷20% and the total deformation of the package 50÷80% with subsequent annealing package consisting of a case at a temperature of 650÷900°C for 40-80 minutes, and then finishing processing obtained after disassembly of packets of sheets.

2. A method according to claim 1, characterized in that in the composition of the charge injected to 40% of titanium waste.

3. A method according to claim 1, characterized in that the sheet molding performed by superplastic deformation at a temperature of 750-800°C and strain rate of 3.5×10-4h-1-4,5×10-4h-1.

4. A method according to claim 1, characterized in that the sheet metal forming performed at room temperature.

5. A thin sheet of two-phase titanium alloy, characterized in that �n manufactured by a method according to any one of claims.1-4.



 

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21 cl, 9 dwg, 2 tbl, 6 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

FIELD: metallurgy.

SUBSTANCE: manufacturing method cold-deformed pipes from α- and pseudo-α-alloys based on titanium involves melting of an ingot, forging of an ingot in β- and α+β-region with ending of forging in α+β-region into an intermediate shell with forging reduction of 2 to 3; piercing is performed at the temperature that is by 30-50°C higher than Tpp, by multiple-cone rolls and a mandrel with the specified geometry with water supply to a deformation zone, rolling of the shell is performed at the temperature that is by 10-90°C lower than Tpp; straightening of the pipe shell is performed at the temperature of 350-400°C, cold rolling is performed with drawing coefficient of 1.5-4.5 at several stages by alternation with intermediate annealing processes at the temperature equal to 600-750°C, and further heat treatment with the ready dimension at the temperature of 580÷650°C.

EFFECT: high mechanical properties of manufactured pipes, as well as high quality of pipe surface.

4 dwg, 3 tbl

FIELD: process engineering.

SUBSTANCE: invention relates to rolling and serves for adjustment of planarity at rolling of aluminium strip or foil. In compliance with this invention, this device comprises pair of working rolls to receive the strip or foil in contact zone between rolls. Besides, it comprises multiple fluid feeders configured to direct said fluid to one or more zones on the surface of at least one roll and heater to heat said one or more zones. Proposed method comprises feeding the cryogenic fluid to one or more zones on roll or rolls surface/surfaces via one or strip or foil feeders. Note here that said zones are distributed uniformly over roll width. One zone or more zones are heated on roll surface by one or more heaters for adjustment of roll radial size over its width.

EFFECT: higher quality of strip or foil.

29 cl, 3 dwg

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: method includes heating of a flat stock and its multi-pass pressing in working rollers. Exclusion of formation of internal defects in rolled metal is achieved by the fact that heating of the stock is carried out to temperature of 750-850°C, and pressing in each of passes is regulated by mathematical dependence.

EFFECT: increased quality of thick-sheet rolled metal from hard-to-deform copper alloys with lower process plasticity.

1 tbl, 6 ex

FIELD: metallurgy.

SUBSTANCE: in compliance with proposed method of rolling thin bands from aluminium Al-Mg or Al-Mg-Mn system alloys fully recrystallised hot-rolled band blank is subjected to rolling. Band blank features cubic texture and depth 9-10 times larger than band final depth. Rolling causes 45-47% reduction at every of two last passes at deformation rate of at least 10 m/s and band coiling temperature of 140-160°C, coil weight making at least 8 t.

EFFECT: higher metal ductility, decreased scatter of mechanical properties.

1 tbl

FIELD: metallurgy.

SUBSTANCE: proposed method comprises hot forming of slab, hot rolling and teat treatment of plate, whereat hot forming if carried out in one step. Immediately after reaching required thickness in slab forming it is quickly cooled to the depth of 20-30 mm at the rate of at least 50°C/min. Subsequent hot lengthwise rolling at performed at first step in α+β-area by partial reduction with deformation degree εi varying from 3% to 5% to total deformation ε=25…30% with breaks between passes of 8 to 12 s. At second step, it is performed in β-area from heating temperature determined by definite formula. At the next step rolling is performed in α+β-are with breaks and heating in lengthwise or transverse directions with total degree of deformation e after every break to 60%.

EFFECT: homogeneous fine-grain microstructure, high and stable mechanical properties, high precision, no surface defects.

FIELD: metallurgy.

SUBSTANCE: invention relates to production of thin sheets from ingot of pseudo-alpha titanium alloy. Proposed method comprises forming ingot of alloy Ti-6.5Al-2.5Sn-4Zr-1Nb-0.7Mo-0.15Si into slab and machining of the latter. Then, said slab is heated to temperature exceeding that of polymorphic transition, deformation and multistep rolling to semi-finished rolled stock with regulated total degree of deformation and degree of deformation in a pass. Sheets are stacked, stacks are rolled to finished size and subjected to multipass rolling with regulated total deformation, sheets are extracted from the stack and subjected to finishing.

EFFECT: high and uniform strength and plastic properties.

1 dwg, 2 tbl

FIELD: metallurgy.

SUBSTANCE: proposed method comprises smelting of alloy, making slab, machining its surface, hot, warm, and cold rolling, sintering and ageing. Smelted is pseudo-beta-titanium alloy with aluminium content not higher than 5.0 wt % and molybdenum equivalent No eq. ≥ 12 wt %, calculated by the following formula: Mo eq. wt % = %Mo + %Ta/4 + %Nb/3.3 + %W/2 + %V/1.4 + %Cr/0.6 + +%Fe/0.5 + %Ni/0.8 + %Mn/0.6 + %Co/0.9. Semi-finished 8-2 mm-thick rolled stock produced in hot and cold rolling is subjected, prior to cold rolling, to quenching at Tpt+(20-50°C) for 0.1-0.5 h with cooling. Cold rolling is performed to sheet thickness of 6-1 mm in signal-phase beta-state in two and more steps in several passes with 1-6%-reduction in one pass and total reduction at every step of 30-50%. Note here that intermediate quenching is carried out between said steps in conditions identical to quenching of semi-finished rolled stock before cold rolling.

EFFECT: high-quality rolled thin sheets.

5 dwg, 2 tbl

FIELD: process engineering.

SUBSTANCE: invention is intended for increasing quality of sheets and ruling out pollution originating in forming special magnesium alloys doped with high-toxicity light-volatile elements that form, in heating and forming, harmful oxides, and may be used in production of sheets for anodes of electrochemical current sources. Proposed method comprises placing round ingot in tubular shell, hearing the workpiece and its hot and warm rolling to requited sheet thickness.

EFFECT: higher quality of sheets and process efficiency.

5 tbl

FIELD: plastic working of metals, possibly manufacture of thin high-strength foil of titanium.

SUBSTANCE: method comprises steps of multi-pass reversing cold rolling and vacuum annealing; repeating cycle; using as initial blank titanium blank with ultra-fine grain structure provided due to intensified plastic deformation by equal-duct angular pressing process; rolling at pitch 15 - 8% for achieving total deformation 70 - 86 % per one cycle; setting number N of cycles necessary for making foil with thickness h according to mathematical expression; realizing vacuum annealing, preferably at temperature 350 -360 C for 0.5 - 1 h. Invention provides possibilities for making titanium foil with thickness up to 10 micrometers.

EFFECT: enhanced strength characteristics of titanium foil of lowered thickness with the same technological platicity7777.

2 cl, 2 tbl

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