SiC/Al Composites Prepared By High Energy Ball Milling

SiC particulate reinforced aluminum matrix composites possesses excellent mechanical properties and physical properties, such as high specific strength, wearproof, low density, low thermal coefficient of expansion, favorable dimensional stability and thermal conduction. It can be widely used into aerospace, military affairs, automobile, electron and athletic sports, SiC/Al composites are paid more and more attention by the industry.In this paper, the SiC/Al composites were prepared by high-energy ball milling. Conclusions are as follows:(1)The effects of the weight fraction of the SiC particles on the mechanical properties of the composite were studied. The results show that the hardness and tensile strength of the SiC/Al composites increased at the beginning and then decreased with the increasing of the weight fraction of the SiC particles which are0%,4%,8%,12%,16%and20%. Through the fracture analysis, it was found the fracture contraction of the SiC/Al composites were more and more small, and the fracture mechanism gradually changed from ductile fracture to brittle fracture with increasing the weight fraction of the SiC particles.(2)The effects of the ball milling parameters on the mechanical properties of the SiC/Al powder and the composites prepared by the SiC/Al powder, including the mass ratio of ball to powder, the stirring shaft speed, the milling time and the amount of process control agent, discussed the best parameters.(3)The effects of the molding pressure on the mechanical properties of the SiC/Al composites were studied, discussed the38MPa was the best molding pressure.(4)The effects of the sintering temperature and sintering time on the mechanical properties of the SiC/Al composites were studied, the results show that the optimum sinter technics was sintered in570℃for60minutes.(5)The effect of the SiC size between23.55μm and0.39μm on the mechanical properties of the SiC/Al composites were compared, the results show that the density, hardness and tensile strength of the16%SiC/Al composites were more superior when used the0.39μm size.(6)The mechanical properties of the SiC/Al, Al2O3/Al and Al/CNTs composites were compared, and these composites were prepared by high energy ball milling. The results show that the SiC/Al composites were best.