WO2017116281A1

WO2017116281A1 - Method of manufacturing metal and composite blanks from sheet materials

Info

Publication number: WO2017116281A1
Application number: PCT/RU2016/000818
Authority: WO
Inventors: Алексей Николаевич КРЫЛОВ
Original assignee: Алексей Николаевич КРЫЛОВ
Priority date: 2015-12-31
Filing date: 2016-11-25
Publication date: 2017-07-06
Also published as: RU2625372C2; RU2015157455A

Abstract

The proposed invention relates to metal forming, and more particularly to combined methods for forming sheet metals, and concerns a method for manufacturing metal and composite blanks from sheet materials for use in mechanical engineering. The present method of manufacturing metal and composite blanks from sheet materials includes simultaneously winding at least two sheets of materials with different strength properties (the tensile stress of one of the materials being higher than the yield stress of the other material) onto a mandrel, and fastening the ends of the material. What is novel is that the winding of the sheet materials, which are wound into rolls, is carried out with the sheet material with the higher strength properties being tensioned to 10-60% of the ultimate strength of the material being wound and with the sheet material with the lower strength properties being tensioned to 0-33% of the ultimate strength of the material being wound, after which the wound layers are welded. The technical result of the proposed invention is an increase in winding density, the production of blanks with a more homogeneous chemical composition and a more uniform distribution of physical and mechanical properties across their cross section, and an increase in the scope of use.

Description

METHOD FOR PRODUCING METAL AND COMPOSITION

LABELING FROM SHEET MATERIALS

The present invention relates to the processing of metals by pressure, and in particular to combined methods of processing sheet metals, relates to a method of manufacturing metal and composite blanks from sheet materials, which can be used in mechanical engineering.

A known method of manufacturing a hollow cylindrical shells (SU 1512739, class. V23K20 / 00, publ. 07.10.89,), including obtaining a multilayer workpiece by winding strip, a thickness of at least 2 mm, fixing the beginning and end of the strip by welding, heating the workpiece and rolling . The method provides an increase in the quality of shells with a diameter exceeding 2000 mm by increasing the stiffness of the wall, the thickness of the inner and outer layer, which gives stability to the workpiece during rolling.

The disadvantage of this method is the narrow scope of its application - only for the manufacture of cylindrical shells. In addition, loose winding requires the adoption of protective measures against oxidation of the wound sheets during subsequent heating under rolling.

A known method of manufacturing reinforced sintered products (ed. St.

829719, cl. C22F3 / 02, C22C1 / 09, publ. 05/25/1981), including folding the reinforcement into a roll by winding it onto the mandrel, placing it in a shell, filling it with subsequent powder and sealing in the radial direction. Before folding, the reinforcement is placed on a substrate of fusible or combustible material, and after placing it in a shell, it is heated to the melting or combustion temperature of the substrate material. The disadvantage of this method are: the difficulty in obtaining a non-porous preform by powder metallurgy and, as a consequence, the decrease in mechanical properties; the complexity of the process - sintering of powder materials requires furnaces with a protective atmosphere or vacuum, as well as the need to manufacture disposable containers; high anisotropy of the physicomechanical properties of the obtained preform.

A method of manufacturing multilayer pipes according to ed. St. N <> 984552, class B21C23 / 08, publ. 12/30/82), including folding the steel tape into a roll with an axial hole, introducing a press needle into the hole in the roll, and then extruding the roll from the container cavity. In this case, the tape is rolled up so that after heating its outer diameter is 3-10% higher than the diameter of the container cavity and the hole diameter is 3-10% higher than the diameter of the press needle, and before extrusion from the cavity of the container, the roll is reduced with a stamp the diameter of this cavity. This allows you to eliminate the gaps between the layers of the rolled billet before pressing, prevent folding and ensure a layer-by-layer uniform plastic flow of the metal of the billet, which improves the quality of the hot-pressed multilayer pipes.

The disadvantage of this method is the narrow scope - only for the manufacture of multilayer pipes. In addition, loose winding requires the adoption of protective measures against oxidation of the sheets during heating by reduction, which complicates the process.

The closest in technical essence and the achieved technical result to the proposed invention is a method for the production of multilayer metal pipes, protected by patent RU 2036063 C1, cl. V23K20 / 00, publ. 05/27/95, adopted for the closest analogue (prototype).

The prototype method includes cutting a metal strip obtained by hot rolling on measured billets immediately after rolling, applying to the measured billet during its winding on a format drum fusible metal in the form of a powder or sheet with a melting point not exceeding 1,100 ° C, when the temperature of the steel sheet is less than the melting point of the fusible metal. To facilitate the assembly process, isolate the pipe from the action of liquids and gases, as well as from corrosion, the metal sheet is wound onto a hollow metal core made of solid metal or from a sheet on the outside of which a ledge is made with a height equal to the thickness of the metal sheet and a length equal to the width measuring workpiece, positioning the end face of the wound material end-to-end with a ledge. The outer surface of the core is made in a spiral, respectively wound layers of high-strength metal sheet. When cooling a multilayer metal pipe, the outer layers due to their linear narrowing compress the inner layers with great force, which increases the diffusion of the fusible metal into layers of a rolled metal sheet with a preliminary stress of the pipe layers.

An advantage and a common feature of the prototype with the invention is the possibility of simultaneous winding of sheets of various materials with different strength properties, which allows to obtain blanks from alloys with different physical and mechanical properties.

However, the prototype is not without drawbacks:

firstly, the winding is carried out by a sheet heated to a high temperature, which complicates the process of winding;

secondly, the use of a hot-rolled sheet for winding, which has higher deviations in thickness difference compared to a cold-rolled sheet, reduces the density of the winding, leads to poor quality of the soldered seam and, as a result, to high anisotropy of physical and mechanical properties;

thirdly, the proposed method does not provide equal strength connection of the wound layers, as a result of which there is a large spread of physico-mechanical properties in the radial direction; s fourthly, the need for a hollow mandrel and low-melting metal narrows the scope of the method.

The objective of the invention is the creation of a new method of manufacturing metal and composite blanks from sheet materials.

The technical result from the use of the present invention is to increase the density of the winding, to obtain blanks with a more uniform chemical composition and with a more uniform distribution of physical and mechanical properties (density, tensile strength, yield strength, elongation, impact strength) over their cross-section, in expansion areas of use.

The problem is achieved in that in a method of manufacturing metal or composite blanks from sheet materials, including the simultaneous winding on the mandrel of at least two sheets of materials with different strength properties, fixing the ends of the material, carry out the winding of sheet materials wound into rolls, with tension sheet material with higher strength properties of 10-60% of the tensile strength of the winded material and with tension sheet material with lower strength properties at 0–33% of the tensile strength of the material being wound, while the tension of a material with higher strength properties should be higher than the yield strength of the material in contact with it with lower strength properties, after which the wound layers are welded; pre-preparing the surface of the winded sheet material and the mandrel, including cleaning from contaminants that interfere with setting; winding is carried out on a cold mandrel; as a mandrel use a bar, rolled, forged, sleeve or pipe; the outer layer is made of a material whose linear expansion coefficient is not more than the linear expansion coefficient of the inner layers; carry out pressure welding of the wound layers by their plastic deformation, or by heating them to a certain temperature, or by their plastic deformation with heating; carry out diffusion welding of wound layers at a temperature of 400 ° C -1350 ° C; heating the wound billet before plastic deformation is carried out to a temperature of 0 ° C-1200 ° C; plastic deformation is carried out after winding the wound layers; plastic deformation of the wound layers is carried out by pressing, rolling, forging; after plastic deformation, heat treatment is performed.

In FIG. 1 shows a schematic drawing of winding two strips, carried out in one of the variants of the proposed method for the manufacture of metal or composite blanks from sheet materials, where: 1 - a mandrel for winding; 2,3,4 - lead, push and support rolls; 5 - rolls of winded materials.

A method of manufacturing metal or composite blanks from sheet materials includes the simultaneous winding onto the mandrel of at least two sheets of materials with different strength properties (the winding tension of one of the materials exceeds the yield strength of the other), securing the ends of the material. At the same time, winding of sheet materials wound into coils is carried out with tension of sheet material with higher strength properties of 10-60% of the tensile strength of the material being wound and tensioning of sheet material with lower strength properties of 0-33% of the tensile strength of the material to be wound, after which carry out the welding of wound layers. In this case, the tension of a material with higher strength properties should be higher than the yield strength of the material in contact with it with lower strength properties.

Pre-carry out the preparation of the surface of the winded sheet metal material and the mandrel, including the cleaning of contaminants that hinder the setting.

The winding is carried out, for example, on a cold mandrel.

As a mandrel use, for example, a bar, rolled, forged, sleeve or pipe. The outer layer is made, for example, of a material whose linear expansion coefficient is not more than the linear expansion coefficient of the inner layers.

Carry out, for example, pressure welding of the wound layers, by their plastic deformation, or by heating them to a certain temperature, or by their plastic deformation with heating.

Pressure welding - pressure welding, carried out due to plastic deformation of the welded parts at a temperature below the melting temperature (GOST 2601-84 Metal welding. Terms and definitions of basic concepts.)

Carry out, for example, diffusion welding of wound layers at a temperature of 400 ° C -1350 ° C.

Diffusion welding - pressure welding, due to the mutual diffusion of atoms in thin surface layers of the contacting parts. Diffusion welding is carried out with a relatively long exposure to elevated temperature and slight plastic deformation. (GOST 2601-84)

Heating of the wound preform before plastic deformation is carried out, for example, at a temperature of from 0 ° C to 1200 ° C.

Plastic deformation of the wound layers is carried out, for example, after winding.

Plastic deformation of the wound layers is carried out, for example, by pressing, rolling, forging.

After plastic deformation is carried out, for example, heat treatment of the workpiece by homogenization annealing, or tempering is performed.

The manufacture of blanks by the proposed method is as follows.

Thorough cleaning of the contact surfaces of the joined sheets is a determining condition for obtaining high adhesion of sheets in

b welding process. To obtain a high-quality connection of the contact surfaces of the layers in the winded billet, they are cleaned of various contaminants that interfere with the setting of metals (oil, adsorbed moisture, oxide films, etc.). Methods of preparing surfaces for pressure welding, including machining, degreasing, etching, calcining, degassing, are described in detail in works on the production of bimetallic compounds and in the manufacture of products by powder metallurgy.

As a starting material for the manufacture of preforms, rolled sheet metal is used. Preference is given to the sheet of cold rolling, since it has smaller manufacturing errors compared to a sheet of similar dimensions obtained by hot rolling.

The winding of sheet materials is carried out, for example, on coilers, lathes, rollers or other type of equipment, allowing to ensure the overall parameters of the workpiece. The winding is carried out on a mandrel, which is used, for example, a bar, rolled, forged, sleeve or pipe, according to one of the schemes used for winding rolled materials (Fig. 1). The number of simultaneously wound materials is chosen at least two, determine the practical feasibility and design of the resulting workpiece. In this case, materials with different strength properties are used (the tension of the winding of a material with higher strength properties should exceed the yield strength of a material with lower strength properties). The winding is performed with a tension of sheet material with lower strength properties of 0-33% of the tensile strength of the material being rolled and with tension of sheet material with higher strength properties of 10-60% of the tensile strength of the material to be rolled. The winding voltage of a material with higher strength properties is chosen in such a way as to obtain a gas-tight connection of the layers due to the flow or compaction of a material with lower strength properties. In this case, the voltage the tension is chosen so as to avoid tearing the sheet, to ensure maximum compression of the previous layer, to obtain a uniform thickness of the wound layers.

The tension force of the winded sheet is determined by the formula:

F „= s xSxK, where

F _H - the tension force of the winded sheet (N);

s - guaranteed tensile strength of the winding material (MPa);

S is the cross-sectional area of the winded sheet (mm ² );

K is the coefficient of tension.

The tension coefficient K depends on the combination of the winding materials, the ratio of the yield strength to the tensile strength of the material of each winded sheet and the linear speed of winding.

The tension coefficient K was established empirically. For sheet material with lower strength properties, the coefficient of tension is K = 0-0.33, and for sheet material with higher strength properties, K = 0.1-0.6.

The stresses arising during winding are determined as follows:

he = F S

The winding speed from 1 to 20 rpm is chosen based on the conditions of the process productivity and the completeness of the flow of plastic deformation between the layers of winded sheets. The lower the winding speed, the more complete is the process of plastic flow of metal in the contact zone. Upon reaching the required diameter of the workpiece, the end of the sheet is fixed to the previous layer, for example, by welding, soldering, gluing, or using a clamp. The last turns (turn) of winding are made of material with a coefficient of linear expansion no more than that of the material of the inner layers. This allows you to increase the compressive strength of the wound sheets during heating. In this case, the outer layer is performed with a margin of safety and ductility to ensure a dense and reliable crimping inner layers during subsequent operations. For this, materials with a large sheet thickness, minimal tension, and high plastic properties are used. After winding, heating and pressure welding of the wound layers is carried out, for example, at a temperature of 400 ° С -1350 ° С (this temperature range provides sintering of workpieces from both low-melting alloys and refractory materials). After winding, or after diffusion welding of the wound layers, they can perform their plastic deformation.

Heating for metal forming can be done on any type of thermal equipment. Carrying out heating at the highest possible speed allows you to effectively use the stress state of the layers for the diffusion-viscous flow of the material. Heating is carried out, for example, in furnaces with an oxidizing or protective atmosphere, as well as in vacuum furnaces. When heating billets of metals and alloys, the main goals are: the formation of physical contact of surfaces at the heating stage; removal of adsorbed gases from internal surfaces. The heating and holding conditions during pressure welding are selected individually for each combination of materials being welded, depending on the surface cleanliness (absence of contaminants, roughness, presence of an oxidized layer), the grain size of the metal, changes in the stress state between layers during heating, and the structural state of the metal (riveted, annealed).

Plastic deformation is performed to activate the welding process of the wound layers, welding of internal defects and giving the necessary shape to the wound workpiece. In the proposed method for the manufacture of blanks, welding is used with free deformation, which implements creep of metals, and welding with forced deformation. Welding with free deformation is realized in the process of heating and holding the workpiece at a heating temperature. Factors contributing to the implementation of welding are: winding, providing compression stress between the layers on yield strength level. Forced deformation welding can be carried out by any known metal forming methods. To obtain a dense defect-free structure of the workpiece, the plastic deformation of the wound layers begins with a broach, since it is the most active operation in relation to the welding of macro- and micro-voids. Other technological factors favoring the welding of defects are described in the literature on forging ingots and difficult to deform materials. Plastic deformation in the manufacture of composite and low-plastic materials by the proposed method is carried out at a temperature below the temperature of occurrence of low-plastic compounds.

Thus, the implementation of the winding of sheet materials with different strength properties with a tension of one material above the yield strength of another material makes it possible to use creep mechanisms already at the winding stage, which makes it possible to eliminate defects on the surface of sheets and compensate for deviations in their thickness difference. Dense winding allows you to heat up the processing of materials by pressure in an oxidizing atmosphere.

The implementation of the winding of sheets of different thicknesses, different chemical composition, structure, level of stress state provides an extension of the areas of use of the proposed method.

The following are examples of specific performance of the invention.

Example 1. The manufacture of the workpiece from intermetallic compounds.

To produce a TiAl-T13AI intermetallic alloy, a mandrel of a similar chemical composition with a preform that has not undergone final sintering with a diameter of 50 mm is simultaneously wound with a VT1-0 titanium tape 0.35 mm thick and 300 mm wide in the annealed state (s = 35-50 kg / mm ² ) and aluminum tape AO 0.25 mm thick, 300 mm wide in the annealed condition (s> 6.0 kg / mm ² ;

Navigation simultaneously from 2 rolls to obtain a workpiece diameter of 400 mm. The winding is performed at a tension voltage of 3.5-5 kg / mm ² for a titanium tape, which is 10-15% of its guaranteed tensile strength; aluminum tape is wound with a tension voltage of 0.15-0.45 kg / mm ² , which is 10-30% of its guaranteed tensile strength. The last 3 layers of winding are performed with a titanium tape. The end of the winding is attached to the last layer. The resulting billet is crimped with a thick-walled clamp from st. 20, heated to a temperature of 600 ° C and grate. Sintering to a temperature of 850 ° С with an intermediate exposure at a temperature of 620 ° С is carried out in a tan state. Homogenization annealing to obtain a more uniform structure is carried out at a temperature of ~ 1250 ° C.

Example 2. Production of a blank of metallographic composite material.

Materials of this group are widely used as anti-friction, friction and contact materials for the transmission of electricity in motion.

The scheme of the technology for producing the antifriction composite material Fe + 8 C is as follows:

- carry out simultaneous winding onto the matrix sleeve 0 50 mm of annealed steel sheet 10 ((ав = 30-41 kg / mm ² ; στ> 21 kg / mm ² ) 0.4 mm thick, 400 mm wide, and thermally expanded graphite foil ( TWG) GF-100 with a thickness of 0.2 mm, a width of 400 mm, a density of 1, 4 g / cm ³ (AB> 0.7 kg / mm ² ; with compression AB> ²⁰ kg / mm ² ); with a tension voltage of 0-0, 15kg / mm ² for TRG foil, which is 0-20% of its guaranteed tensile strength; with a sheet tension of 10 from 10-18-18 kg / mm ² , which is 40-60% of its guaranteed tensile strength blanks with a diameter of 100 m;

- the resulting billet is installed in the holder of the matrix, heated to a temperature of 500 ° C. Produce heating of the workpiece in the holder to 530 ° C;

P - carry out the pressing of the wound workpiece at a temperature of ~ 530 ° C to the size: outer diameter 60 mm, inner diameter 50 mm;

- diffusion welding of the obtained workpiece at a temperature of 1050-1100 ° C.

Example 3. The manufacture of blanks from composite materials based on refractory compounds.

To obtain carbides, steels of the type (Ferro-TiC), powder metallurgy methods are currently used. The production of these materials is also possible by the method of winding.

Consider getting a preform of 80% TiC + 20% Ni-Mo binder.

Materials used for winding:

- a titanium sheet VT 1-0 0.6 mm thick, 400 mm wide, annealed (AB = 35-50kg / mm ² );

- a sheet of alloy 81 NML with a thickness of 0.1 mm, a width of 400 mm, annealed ((s = 60-70kg / mm ² ; from> 25kg / mm ² );

- SIGRAFLEX thermally expanded graphite foil with a thickness of 0.15 mm, a width of 400 mm, a density of 1.3 g / cm ³ (s> 0.7 kg / mm ² ; with compression> ²⁰ kg / mm ² ).

The winding is carried out on a mandrel (bar) with a diameter of 40 mm of a similar chemical composition with the resulting workpiece not past the final sintering.

The winding is carried out from 4 rolls so that the compacted graphite material is between the metal sheets. The winding is performed at a tension voltage of 12-18 kg / mm ² for 81NMA alloy sheets and VT 1-0 titanium sheet, which is 20-30% and 35-50% of their guaranteed tensile strengths, respectively. Graphite foil is wound with a tension voltage of 0-0, 15 kg / mm ² , which is 0-20% of its guaranteed tensile strength. The winding is carried out until a workpiece diameter of 150 mm is obtained. The last 3 layers of winding are performed with a titanium tape. The end of the winding is attached to the layer against it. The resulting billet is installed in the holder of the matrix, heated to a temperature of 400 ° C. The billet is heated in a holder to 400 ° C. Pressing the workpiece to a diameter of 50 mm is carried out at a temperature of 400 ° C. Diffusion welding is carried out in the presence of a liquid phase formed during heating and holding at a temperature of 1300-1350 ° C.

Example 4. The manufacture of a billet of copper-aluminum layered composite material.

Sheets are simultaneously wound on a bar from an AMgb alloy with a diameter of 30 mm and a length of 600 mm:

- AMgb aluminum-magnesium alloy with normal cladding annealed 0.5 mm thick and 600 mm wide. The tensile strength of the sheet AMGB - (AB> 31 kg / mm ² ); clad layer - (s> 6kg / mm ² ; from = 1.5-Zkg / mm ² ).

- technical copper Ml in annealed condition with a thickness of 0.4 mm and a width of 600 mm. The tensile strength of the sheet is Ml - (ав = 20-27kg / mm ² ).

The winding is carried out simultaneously with 2 rolls to obtain a workpiece diameter of 250 mm. Coiling of clad aluminum-magnesium and copper tape is carried out at a tension voltage of 3.5-5 kg / mm ² , which is 11-16% and 17.5-25% of their guaranteed tensile strengths, respectively. The last 5 layers of winding are made of technical copper tape. The end of the winding is attached to the last layer.

Compression of the wound workpiece through a conical matrix is carried out without preheating to a workpiece diameter of 50 mm. The resulting preform is released at a temperature of 170-200 ° C.

Example 5. The manufacture of large-sized billets of steel 12X18H10T.

For the manufacture of a workpiece with dimensions: outer diameter 1100 mm, inner diameter 550 mm, length 1000 mm, two cold-rolled sheets of steel are simultaneously wound onto a pipe made of TP304 630x24 steel according to ASTM A312 / A312M-06 steel 12X18H10T 3,5x500 to obtain a diameter of 1500 mm. Materials in different structural conditions are used: one roll in heat-treated with s> 54 kg / mm ² and στ> 21 kg / mm ² ; another in semi-guaranteed with av> 75 kg / mm ² . The winding of the heat-treated sheet is performed at a tension voltage of 12-18 kg / mm ² , which is 22-33% of its guaranteed tensile strength and for semi-cured sheet 25-30 kg / mm ² , which is 33-40% of its guaranteed tensile strength. The winding of the last two layers of the workpiece is performed by heat-treated material with welding of the end to the last turn. The outer layers of the wound workpiece are wrapped with a heat-insulating material of mullite-siliceous felt with a thickness of 30 mm in two layers. Heating to the forging temperature is carried out at the highest possible speed. The temperature range of forging is 1200-850 ° C.

Example 6. The manufacture of the workpiece magnesium-aluminum layered composite material.

At the same time, a tape is wound onto a bar from an AMgb alloy with a diameter of 50 mm and a length of 200 mm:

- AMgb aluminum-magnesium alloy with normal cladding annealed with a thickness of 0.5 mm and a width of 200 mm. The tensile strength of the sheet AMgb - (s> 31 kg / mm ² ); clad layer - (s> 6 kg / mm ² ; at = 1.5-3 kg / mm ² ).

- MA2-1 magnesium alloy in the annealed state, 0.6 mm thick and 200 mm wide. The tensile strength of the sheet MA2-1 - (s> 26 kg / mm ² ).

The winding is carried out simultaneously with 2 rolls to obtain a workpiece diameter of 400 mm. Coiling of clad aluminum-magnesium and magnesium tape is carried out at a tension voltage of 3.5-5 kg / mm ² , which is 11-16% and 13.5-20% of their guaranteed tensile strengths, respectively. The resulting billet is crimped with a thick-walled clamp from article 20, heated to a temperature of not more than 440 ° C and zeuvolen. Diffusion welding is performed in a vacuum furnace at a temperature of 420-440 ° C.

Claims

Formula of the Invention

1. A method of manufacturing metal and composite billets from sheet materials, including the simultaneous winding on the mandrel of at least two sheets of materials with different strength properties, fixing the ends of the material, characterized in that the winding of sheet materials wound into rolls, with sheet tension material with higher strength properties of 10-60% of the tensile strength of the winding material and with tension sheet material with lower strength properties of 0-33% of the tensile strength chnosti wound material, the tension of a material with a high strength properties must be higher than the yield strength of the material contacting them with lower strength properties, whereupon welding is performed wound layers.

2. The method according to claim 1, characterized in that the surface of the winding sheet material and the mandrel are preliminarily prepared, including cleaning of contaminants that interfere with setting.

3. The method according to claim 1, characterized in that the winding is carried out on a cold mandrel.

4. The method according to p. 1 characterized in that as a mandrel use a bar, rolled, forged, sleeve or pipe.

5. The method according to p. 1 characterized in that the outer layer is made of a material whose linear expansion coefficient is not more than the linear expansion coefficient of the inner layers.

6. The method according to p. 1 characterized in that they carry out pressure welding of the wound layers by plastic deformation, or by heating them to a certain temperature, or by their plastic deformation with heating.

7. The method according to p. 1 and p. 6 characterized in that the diffusion welding of the wound layers is carried out at a temperature of 400 ° C -1350 ° C.

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8. The method according to p. 6 characterized in that the heating of the wound workpiece before plastic deformation is carried out to a temperature of 0 ° C-1200 ° C.

9. The method according to p. 6 characterized in that the plastic deformation is carried out after winding the wound layers.

10. The method according to p. 6 and p. 8 characterized in that the plastic deformation of the wound layers is carried out by pressing, rolling, forging.

1 1. The method according to p. 6 and p. 8, characterized in that after plastic deformation, heat treatment is performed.

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