Technology for producing wear-resistant bimetal bearing based on cast aluminum

Abstract

The paper presents the results of research the new technological process for producing bimetallic materials in the composition of “aluminum cast alloy - sintered iron powder” by the method of joint stamping of liquid metal. The purpose of this research is obtain parts with high wear-resistant properties, special sintered powder materials are used, which have an internal porosity to retain lubricant. However, such materials do not fit well with traditional aluminum alloys. This problem is may be solved by creating new bimetallic alloys, part of which is an outer casing, and the other materials is the functional bearing. To accomplish this task, we conducted a study of a new technology for joint stamping of liquid metal. In order to optimize and increase the reliability of the experiment, the pressing pressure, the pressure holding time, and the tooling temperature of the matrix were taken as quantitative factors. The effect of the applied pressure on the mechanical properties of the base material and the facing layer was determined on a longitudinal section of the obtained samples by the Vickers method. It was revealed that the gradient of increasing hardness is directed to the outer radius of the workpiece, that is, to the opposite crystallization front. The high level of bimetal adhesion is explained by the presence of a uniform moderate zone of mutual solubility, including due to the violation of the porous surface layer of the powder billet.