Effect of heat treatment on friction properties of functional graded materials fabricated by fine particle peening

Author:  Ando, Usami
Source:  Conf Proc 2011: ICSP-11 South Bend, IN USA (pgs. 317-322)
Doc ID:  2011053
Year of Publication:  2011
Abstract:  
Abstract This present study describes the effect of heat-treatment to the functional graded material fabricated by fine particle peening for improving tribological properties. The application of heat-treatment is to control properties of functional graded regions where the fine particles were migrated. Fine tungsten carbide particle used for the formation of the functional graded surfaces were coated with the steel beads and then were used to penetrate the alloy steel sample surface. The heat-treatment was carried out at various temperatures. The surface and the cross section after heat treatment were analyzed with SEM/EDX, and the hardness was measured by micro-indentation. The change of the micro structure and the increase in the hardness were found in the heat treated specimen. Tribological properties of specimens were evaluated with the thrust type rolling contact experiment under lubricated condition. Hardened chromium alloy steel (SUJ2) was used as the rolling element. As a result, it was confirmed that the peened and heat treated specimen having higher hardness showed not only superior wear resistance but also lower traction coefficient than the mirror surface. Moreover, the damage of matching materials was reduced to the same level as the mirror surface. Keywords Fine particle peening, Heat-treatment, Functional graded material, Tribology, Melting and penetration