Semi-Solid Processing of Nano-SiCP/ Al-Si Composites and Mechanical Properties with Rheo-Casting
Generally nano-SiC particles are difficult to be added into molten aluminum metals because of poor wettability. Nano-SiC particles reinforced A356 aluminum alloy composites were prepared by a new process, i.e., a molten-metal process combined with mechanical stirring at semi-solid state and ultrasonic vibration method. The nano particles were β-SiCp with an average diameter of 40 nm, and pre-oxidized at about 850°C to form an oxide layer with thickness of approximately 3.6 nm. The SEM analysis results show that nano-SiC particles are dispersed well in the matrix and no serious agglomeration is observed. The tensile strength and elongation of the 2wt.% nano-SiCp/A356 composite in as-cast state are 259 MPa and 5.3%, and they are improved by 20% and 15% respectively compared with those of the A356 alloy.
Qiang Zhu, Ahmed Rassili, Stephen P. Midson and Xiao Gang Hu
S. S. Wu et al., "Semi-Solid Processing of Nano-SiCP/ Al-Si Composites and Mechanical Properties with Rheo-Casting", Solid State Phenomena, Vol. 285, pp. 33-38, 2019