Automotive starter carbon brush material and preparation method thereof

Abstract

The invention relates to an automotive starter carbon brush material and a preparation method thereof. The carbon brush material is prepared from, by mass, 60-64 parts of copper powder, 32-38 parts of graphite, 3-6 parts of molybdenum disulfide, 1-1.5 parts of tin powder, 0.4-0.6 part of carbonyl iron powder and 0-0.9 part of a friction component; and the graphite is a combination of micro-fine graphite and colloidal graphite, and the mass ratio of the micro-fine graphite to the colloidal graphite is (0.66-1.5): 1. According to the automotive starter carbon brush material and the preparation method thereof, by introducing the carbonyl iron powder to strengthen a matrix, the micro-fine graphite and the colloidal graphite in different particle sizes are selected to be matched so that the graphite distribution uniformity and the interface bonding capacity between the graphite and the matrix can be improved, a specific preparation process is used in cooperation, and the carbon brush material with good electric conductivity and abrasion resistance is obtained; and meanwhile, a carbon brush has good heat conduction performance and mechanical performance, the service life of the carbon brush is prolonged, and the application prospects are wide.

Description

technical field [0001] The invention relates to the field of material preparation, in particular to an automobile starter carbon brush material and a preparation method thereof. Background technique [0002] Carbon brush is an important component of the motor. Its function is to conduct current between the fixed part of the motor and the rotating part of the commutator or collector ring. Its performance directly affects the normal operation of the motor. Compared with ordinary mechanical friction and wear, carbon brush materials have a variety of mechanical friction and wear mechanisms during the operation of the motor, and are accompanied by arc ablation and electrical wear. The wear conditions of automobile starter motors are complex, requiring carbon brush materials to have large current-carrying capacity, excellent reversing performance and sliding contact performance, while conventional carbon brushes will experience increased wear and severe arc ablation under high-den...

AI Technical Summary

Problems solved by technology

However, the hardness and bending strength of the carbon brush material prepared by it are still insufficient

[0005] Han Shaochang et al. changed the wettability of copper and graphite by adding Cr. Although the resistivity of the composite material was reduced to a certain extent, the degree of improvement in the wear resistance of the material was limited (see "Chromium Improves Copper and Carbon-Graphite Materials The role of wettability", Han Shaochang, Li Xueqian, Hunan University Journal, 1998(5):30-33)

[0006] In addition, the copper plating treatment of graphite has made up for the previous deficiencies to a certain extent. It not only realizes the uniform distribution of copper and graphite, but also improves the electrical conductivity, flexural strength and ductility of the composite material, but the density of the composite material decreases. Severe, resulting in insufficient carbon particles to participate in the formation of the lubricating film during the friction and wear process, which is not conducive to the stability of the commutation and the life of the carbon brush material

The degree of deformation of the copper matrix during wear can be improved by adding SiC particles, but SiC, as a ceramic phase particle, will adversely affect the electrical conductivity of the composite material; SiO 2 Although the introduction of the composite material improves the friction and wear performance of the composite material, it can introduce oxidation wear, which will also have an adverse effect on the operation and stable commutation of the motor

Images