RU2377107C2 - Manufacturing method of bimetal with antifriction alloy on basis of aluminium for bushes of friction bearing - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: invention can be used at receiving of bimetallic sheets and strips from steel, plated by antifriction alloy on the basis of aluminium, of thickness more than 6.2 mm, provided for manufacturing of friction bearing. At manufacturing of steel basis received strips are treated by butts at planning machine and annealed in protective environment at 690 °C. Then it is implemented flattening of strips, its double-ended grinding and cleaning of contact surface up to roughness in the range Ra 6.3-12.5 mcm. After preparation of plating layer and assembling of packet it is implemented cold rolling one-passed with clamping 41-43 % and flattening bimetallic semi-finished rolled products. After following annealing at temperature 355°C during 2 h 45 min it is implemented cutting up to finished dimension and quality control.

EFFECT: invention provides conditioning of bimetal and enhancement ensured by increasing of nomenclature by thickness of bimetal.

3 cl, 1 ex

Description

The invention relates to rolling production, namely to the production of bimetallic sheets and strips of steel, clad with an antifriction alloy based on aluminum, intended for the manufacture of plain bearings.

There is a known method of manufacturing bimetal for plain bearing shells (RU 2244612 C2, 23 K 20/04), including preparing the surfaces of the starting materials, assembling the bag, cladding by cold rolling with compression of 50-70%, heat treatment, the bag is assembled from layers of steel and copper-plated on both sides of the bronze, the thickness of the layers of copper in copper-plated bronze is determined from the condition of providing in the finished bimetal a copper sublayer with a thickness of not more than 60-80 microns, bimetal for plain bearing shells is made according to the technological scheme and equipment for cold rolling of bimetal steel-alloy AO20-1, heat treatment is carried out at a temperature of 610-630 ° C in a protective gas environment.

However, this method does not allow to obtain bimetal with an antifriction alloy on an aluminum basis with a thickness of more than 6.2 mm.

For the closest analogue, a method of manufacturing bimetal for sliding liners was adopted (Drought P.F. Bimetal hire / P.F. Zasuha, V.P. Korshchikov, O.B. Bukhvalov, A.A. Ershov. - M .: Metallurgy, 1971 , - 264 p.), Including the preparation of a steel base by sequential etching, washing, stripping, drying, calibration, trimming, cutting to measured lengths, chemical degreasing, annealing and stripping of the contact surface, preparation of a clad layer by chemical degreasing and cleaning of the contact surface bag assembly, cold plaki bimetal rolling, dressing, intermediate annealing, rolling to the finished size, dressing, final annealing, cutting to the finished size and quality control of the bimetal.

The disadvantage of this method is the inability to obtain bimetal with an antifriction alloy on an aluminum basis with a thickness of more than 6.2 mm.

The technical result is achieved by the fact that in the method of manufacturing bimetal for plain bearings, including the preparation of a steel base from steel grades 08PS, St3, St10 by cutting steel, processing edges, annealing, straightening strips, double-sided grinding, cleaning the contact surface, assembling packages, cold cladding, dressing of bimetallic rolling, annealing, cutting to finished size and quality control. Preparation of a steel base includes the processing of strips at the ends, annealing, dressing, double-sided grinding on a plane, cleaning of the contacting surface. Annealing of the steel base is carried out at a temperature of 690 ° C for 24 hours. Cladding to the required size is carried out with a compression of 41-43% in one pass.

The method is as follows.

To obtain bimetal, they take a steel base and a clad anti-friction alloy based on aluminum. A steel base is preliminarily subjected to steel cutting, steel strip processing at the ends, steel strip annealing in a conveyor electric furnace with a protective atmosphere, straightening of steel stripes and two-sided grinding of steel stripes along a plane, cleaning of the contact surface of the steel base. The cladding layer is degreased and the contact surface is cleaned. From the prepared - steel base and cladding layer, packages for cold cladding are collected, which is carried out with compression of 41-43% in one pass. After rolling, the bimetallic strips are annealed in electric furnaces, they are straightened and stripped of the steel base, cut to specified sizes and quality control is carried out.

The technical result - improving the quality of bimetal and expanding technological capabilities by increasing the range of thickness of the bimetal.

Example. Designation of bimetal steel + antifriction alloy AO20-1 with a size of 9.8 ^+0.22 × 8.4 ^{± 0.14} × 155 mm, where 9.8 ^+0.22 is the total thickness of the bimetal, 8.4 ^{± 0.14} - the thickness of the steel base in bimetal, 155 mm is the width of the bimetal strip.

We obtain bimetal for plain bearings of steel bearings + antifriction alloy AO20-1 with a size of 9.8 ^+0.22 × 8.4 ^{± 0.14} × 155 mm by cold cladding.

To obtain bimetal, we use cold-rolled steel of the St10 brand with a thickness of 16 mm, cold-rolled alloy AO20-1 with a thickness of 2.6 ^+0.05 mm.

We subject the steel base to cutting steel, processing strips at the ends on a longitudinal planing machine, obtaining steel strips 16 × 155 × 1450 mm in size, annealing in a protective atmosphere at a temperature of 690 ° C, straightening steel strips, double-sided grinding of strips along the plane to the thickness of steel 14 , 25 mm and cleaning the contact surface of the steel with an endless grinding belt 3050 × 215 grain 50 TU U3.02-0022225-015-95. The roughness of the cleaned surface should be within the range of Ra 6.3 ÷ 12.5 μm according to GOST 2789-73.

The cladding layer - cold-rolled alloy AO20-1 is degreased in trichlorethylene in a special installation for removing grease stains and cleaning the contact surface with three rotating brushes made of steel wire with a diameter of 0.3 mm to a metallic sheen.

After cleaning the contact surfaces of the steel base and the cladding layer of the AO20-1 alloy, we form steel packets of 14.25 × 155 × 1450 mm in size + AO20-1 alloy of 2.6 × 153.5 × 1450 mm in size. The total thickness of the bag is 16.85 mm. Bimetallic strips are rolled in one pass with 41-43% compression at the DUO 900 rolling mill. After cold-rolled bimetallic strips, we anneal them in a tunnel electric furnace at a temperature of 355 ° C for 2 hours 45 minutes at the set temperature. The purpose of annealing is to relieve internal stresses after rolling and for uniform distribution of structural components in bimetal. Annealed bimetallic strips from the side of the steel base are subjected to stripping with rotating steel wire brushes, quality control of bimetal, cutting to a given size and preservation.

Quality control of bimetal with АO20-1 alloy measuring 9.8 ^+0.22 × 8.4 ^+0.14 × 155 mm, lot No. 95 includes:

1. Checking the geometric parameters of the bimetallic strips:

- strip thickness - 9.8 ^+0.22 mm - micrometer ML GOST 6507-90;

- strip width - 155 mm - metal ruler GOST 427-75;

- strip length - 1450 mm - tape measure L = 3 m GOST 7502-98.

2. Checking the ratio of layers in bimetal:

- total thickness of bimetal - 9.8 ^+0.22 mm - micrometer ML GOST 6507-90;

- thickness of the antifriction layer - 1.4 ^{± 0.14} mm - NATI induction thickness gauge No. 7034 or multifunctional geometric parameters measuring device Constant K5;

- the thickness of the steel base is determined by mathematical calculation:

steel base thickness = total bimetal thickness - thickness of the antifriction layer, i.e. 9.8 ^+0.22 mm - 1.4 ± ^0.14 = 8.4 ^{± 0.14} mm;

- the thickness of the technological sublayer of aluminum - 0.10 ÷ 0.11 mm - is determined metallographically on thin sections.

3. Checking the quality of adhesion of the layers in the bimetal is carried out according to the method TU 23.1.142-98:

- test the adhesion of the layers when checking for shear shear using a tensometer - 8.8 ÷ 9.2 kgf / mm ² ;

- with the help of a chisel.

4. Checking the chemical composition of the antifriction alloy in bimetal:

- GOST 14113-78 Aluminum antifriction alloys. Stamps;

- Tin - 19% - Methodology for measuring tin content MVI 1-2004;

- Copper - 0.80% - GOST 11739.13-98. Cast aluminum and wrought alloys. Methods for the determination of copper;

- Iron - 0.24% - GOST 11739.6-98. Cast aluminum and wrought alloys. Methods for determining iron;

- Titanium - 0.048 ÷ 0.056% - GOST 11739.20-99. Cast aluminum and wrought alloys. Methods for the determination of titanium;

- Silicon - 0.12% - GOST 11739.7-99. Cast aluminum and wrought alloys. Methods for determination of silicon;

- Zinc - 0.11% - GOST 11739.13-98. Cast aluminum and wrought alloys. Methods for the determination of zinc.

5. Checking the hardness of the steel base according to GOST 9013-59.

- Rockwell hardness gage TK-2 GOST 9013-59- 88; 90; 88 HRb.

6. Checking the hardness of the antifriction alloy according to GOST 9012-59.

- Brinell hardness gage TSh-2M GOST 9012-59 - 31.5; 31.7; 31.7.

7. Checking the roughness of the steel base according to GOST 2789.

- Profiler mod. 283 GOST 19300-86 or profilometer mod. 171621.

Claims (3)

1. A method of manufacturing bimetal for plain bearing shells, consisting of a steel base and a cladding layer of an aluminum-based antifriction alloy, with a thickness of more than 6.2 mm, comprising preparing a steel base by cutting steel, processing strips at the ends on a planer, annealing in a protective atmosphere at 690 ° С, straightening strips, double-sided grinding of strips and cleaning of the contact surface to a roughness within R _a 6.3–12.5 μm, preparation of a clad layer, assembly of the bag, cold rolling of the bag in one a passage with compression of 41-43%, dressing of a bimetallic rolled product, its annealing at a temperature of 355 ° C for 2 hours 45 minutes, cutting to a finished size and quality control. 2. The method according to claim 1, characterized in that the steel base is made of steel grades 08PS, or St3, or St10, and the cladding layer is made of alloy AO20-1. 3. The method according to claim 1, characterized in that the double-sided grinding and cleaning of the contact surface of the strips of the steel base is performed with an endless grinding belt 3050 × 215 with grain 50.