Microstructures and mechanical properties of A356-SiCp/A356 cladding composite materials prepared by vacuum Solid-Liquid casting

A356-SiCp/A356 cladding composite materials were prepared by vacuum solid-liquid casting. The interfacial bonding, microstructure, and mechanical properties of this cladding composite material were investigated. The microstructures indicated that there was a good metallurgical combination interface between A356 and SiCp/A356 of the cladding composite material. The tensile tests showed that the bonding strength of the interface was lower than that of the two materials, but fracture occurred on the A356 side as the macrointerface perpendicular to load, while the tensile strength of A356 was higher than that of the cladding composite material. This fracture phenomenon could be explained by the remelt mechanism and grain coarsing mechanism. As a result of the topmost layer of the A356 alloy in contact with the SiCp/A356 composite slurry being remelted when the SiCp/A356 composite slurry was poured, an inseparable metallurgical combination interface was formed, and alpha-Al grains and eutectic Si on the A356 side near the interface were coarser than those on the interface. The results of this research can provide a reference for manufacturing automotive brake discs with cladding composite materials.