| Along with the fast development of the transportation industry, the equipments also turn to the direction of large-scale, high speed, the heavy load, and the high security. So the standard of the operational-performance of the friction material is being set more and more higher. Recently, researchers are turning their attention to a new type of composite material-interpenetrating phase composites. This combination gives full play to the advantages of both the reinforced phase and the matrix phase by interpenetrating and mutual supporting, therefore brings the outstanding physical, chemical and mechanical performance.Leading Cu into the SiC carcase to produce the 3D-Meshy SiC/Cu composite material. Some researches of this material on the mechanical property, the interface reaction, the influence of heat treatment and the friction and wear property were did. The results are as follows:(1) Bending strength of the 3D-Meshy SiC/Cu composite material reached 225.9MPa, compression strength reached 199.9MPa, and tensile strength to 19MPa. Interpenetration of the SiC reinforced phase and the Cu matrix phase resulting the mutual supporting when the load is added, so the mechanical property improved a lot.(2) Interface reaction existed during the casting procedure of the 3D-Meshy SiC/Cu composite material. The interface reaction mainly divides into three steps:(1) SiC decomposed into Si and C; (2) SiC and C produced by the SiC reacted with the Cu matrix, resulted variety interface products; (3) solid phase diffusion. The main interface products include Cu4Si,C,TiC,V-C,Cr-C and Cr-Si compound. There are mainly four interface reaction region from the SiC framework to Cu matrix:the first region include Cu4Si,C,Ti-C and Cr-C compounds; The second region is the transition zone of the first and third region; The third region mainly are TiC and V-C, and the fourth is Cr-Si compounds; The third and fourth regions are at the forefront of the interface reaction region, which blocked the atoms diffusion of the two sides of interface, and restrained the interface reaction.(3) After the 3D-Meshy SiC/Cu composite material was heated at 700℃and held for 30,60,90,120min, no new interface compounds or phases were detected. The heat treatment made no big influence to the other element's distribution of the interface region,except changing C's distribution in the first region, as the increase of the heat treatment time, large-scale graphite phase began to disappear and turned to dispersely distributed particles; Cu has oxidized gradually into Cu2O and CuO during the heat treatment process; After the heat treatment, the Cu substrate's grain size increased, and the density of the twin crystal also increased; show The diffusion coefficient D of Cu was 2.76×10-14 m2·s-1 calculated through the Fick diffuse law. (4) Simulation of braking experiment on passenger vehicle has been carried out by using the 3D-Meshy SiC/Cu as Static ring and cast iron as moving ring. The results showed that: with the increase of the rotational speed, the average friction coefficient and acceleration reduced while the braeking time and braking distance increased. with the increase of the pressure, the average friction coefficient,braking time and braking distance all reduced while the acceleration increased; The abrasion mechanism in the braking process mainly is abrasive wear, while follwing with some additive wear, and, the material transport from cast iron ring to 3D-Meshy SiC/Cu ring occured. The 3D-Meshy SiC was able to support the load applied onto the sliding surface and restricted the plastic deformation and high-temperature softering of the Cu matrix, thus it showed nice friction and wear properties.
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