Production technology of steel-copper bimetal composite material for bearing manufacture

Abstract

The invention discloses production technology of a steel-copper bimetal composite material for bearing manufacture. The production technology comprises steps of blanking, surface treatment, finish rolling before sintering, protection sintering, finish rolling, secondary protection sintering, oil aperture processing, finish rolling, and smoothing. The beneficial effect of the production technology is that copper powder apparent density is stabilized to optimize pre-processing of a steel plate, and protection sintering and finish rolling are strictly controlled, so that thickness, binding strength, and physical properties of an obtained plate is greatly improved, compared with that of the original steel plate. Thickness tolerance is improved from + / -0.004 mm to + / -0.002 mm; the rate of dropping of a copper powder layer in a bending test is reduced; and possibility of a bi-metal layering phenomenon is less during finish rolling. Through the optimized technology, physical properties of a bimetal bearing are improved with increased quality of the plate.

Description

technical field [0001] The invention relates to the field of bimetallic composite materials, in particular to a production process for producing bearing steel-copper bimetallic composite materials. Background technique [0002] At present, the steel-copper bimetallic composite material is an ideal anti-friction material, which has both the wear resistance of copper and the high strength of steel, and is an ideal material for the production of bimetallic bearings. The steel-copper bimetal composite material manufactured by powder metallurgy method is made of high-quality low-carbon steel as the matrix, sintered tin bronze powder on the surface, and is made through multiple sintering and rolling. The composite materials used in existing bimetallic bearings are mainly formed by loose sintering. The bulk density of copper powder is different, resulting in unstable quality of the composite material. The low bulk density of copper powder will cause large sintering shrinkage of cop...

AI Technical Summary

Problems solved by technology

The composite materials used in existing bimetallic bearings are mainly formed by loose sintering. The bulk density of copper powder is different, resulting in unstable quality of the composite material. The low bulk density of copper powder will cause large sintering shrinkage of the copper alloy and reduce the strength of the alloy layer. Low, low hardness, no rolling amount or very small, surface roughness does not meet the requirements

If the bulk density is too high, the porosity of the copper powder will decrease, the air permeability will decrease, the infiltration angle will decrease during the secondary sintering, and the phenomenon of "sweating" will easily occur, which is not good for the sintering diffusion of the alloy.

Due to high load, special movement form, insufficient oil supply, and different wall thicknesses, the bimetallic bearings produced by this kind of materials have serious wear, copper powder layer falling off, and even shaft seizure.

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