Study On 3D-network SiC Ceramic Reinforced Al Matrix Co-Continuous Composites

With the continuous fast development of the transportation industry, the corresponding equipment also turned to the direction of heavy load, high speed and the high security. Therefore, the harsher requirement for the performances of brake materials was put forward. Recently, a new type of composite,3D-network ceramic/metal co-continuous composites with isotropy was concerned about by more and more researchers. Because the 3D-network ceramic and matrix phase metal are continuous support and mutual penetration inside of the composites, there were also no isolated phases in three-dimensional space. This combination gives full play to the advantages of both the reinforced ceramic phase and the matrix metal phase by interpenetrating and mutual supporting, therefore brings the outstanding physical properties.In this paper, the 3D-network SiC ceramic/Al co-continuous composites (C4 material) were produced by In-Situ Reactive Pressureless Infiltration (ISRPI) technique. Al alloy powders and some specially components which improve the wetting ability between ceramic/metal were put into the pores of ceramic. Microstructure and mechanical properties of composites were discussed in this paper by X-Ray Powder Diffraction, Scanning Electron Microscope, Material Testing Machine, Laser Thermal Analyer and so on.Using ISRPI technique, the best ratio of aluminum alloy powders is Al-10Mg,The highest relative density of composites was up to 90.42% and corresponding thermal conductivity was 167.42W/m-K. The 3D-network SiC ceramic and matrix phase Al alloy combined well in the interface. However, the interface of composites could be divided into three zones and two interfaces. They are named matrix Al alloy zone, interfacial reactions zone, reinforced SiC ceramic zone, interface 1 zone and interface â…¡ zone, respectively. The main products of interfacial reactions were MgAl2O4 and Mg2SiO4, moreover. There are also SiC, Al, new generation of compound SiCN ceramic and less amount of brittle compound Al4C3 And using the 45# steel as friction ring, the braking friction material experiments were simulated with composites as friction block. The results show that, the friction factor of composites gradually decline with the increase of rotational speed. The value tend to be stable when the rotational speed is higher than 160r/min. This is because that the temperature of C4 materials increased with the increase of speed, and the resist plastic deformation ability of C4 material become low. However, because of its unique 3D-network interpenetrating structure, the hard phase SiC ceramic play an important role on the wear surface to form a micro convex body and bearing effect. Therefore, the friction factor of C4 materials tend to be stable.