Study On Bonding And Post Treatment Of Steel-backed Copper-graphite Bearing Plate

ABSTRACT:In order to develop a high-property steel-backed copper-graphite bearing plate needed urgently in national economy, the semi-solid casting-rolling forming and theoretical research work about steel-backed copper-graphite bearing plate was carried out in this paper.The electromagnetic-mechanical stirring technique with a two-layered stirrer was developed and the basic theory of slurry preparation was formed. A copper-graphite slurry with uniform distribution of graphite (10vol%) and SiC (lvol%) particles was prepared by this technique successfully. A new way to solve the key problem, namely, preventing particles from floating and realizing structural homogenization of slurry, was explored in preparation of copper-graphite slurry.The reasonable semi-solid processing condition of copper-graphite composite was determined and the problem of particle segregation in conventional casting of copper-graphite composite was solved.The relationship between mechanical property, structure and bonding parameters was established, the reasonable technique was optimized and the bonding mechanisium was determined in semi-solid casting-rolling of steel-backed copper-graphite bearing plate.Post treatment of interfacial residual stress was carried out, the true interfacial shear strength, the relationship model and the reasonable technics were got. A simple, low cost and little energy waste two-pass rolling post treatment technique which can substitute stress-eliminating annealing post treatment was developed.In this research, a high property of140MPa which is50%higher than90MPa in particle sintering rolling was achieved. It can be seen that a new way to prepare high-property steel-backed copper-graphite bearing plate for the need of "fast running and over loading" was explored and a firm foundation for widening the application of steel-backed copper-graphite bearing plate in national economy was laid.