Microstructure and properties of copper matrix composites reinforced by nano-SiC and nano-Al_2O_3 particles

摘要

Copper/silicon carbide composites (Cu/SiC) and copper/alumina composites (Cu/Al_zO_3) were fabricated by the powder metallurgy method. The influence of reinforcement particles contents on the relevant properties of the composites and the microstructure of Cu/SiC and Cu/Al_2O_3 composites were studied. The reinforcement effects of nano-SiC and nano-Al_2O_3 particles were compared. The experimental results show that with the increase of the amount of nano-SiC and nano-Al_2O_3 particles, the density of the both composites decreases, the resistivity increases, whereas the hardness increases firstly and then drops. The softening temperatures of the composites are above 700℃ which is far higher than that of the pure copper, leading to the improvement of the thermal stability of the composites at high temperatures. Considering all factors, the reinforcement effects of nano-SiC are better than those of nano-Al_2O_3 when their contents are the same in the copper matrix.