采用机械搅拌铸造法制备了包覆镍碳纳米管(CNTs)/AM60复合材料,研究了包覆镍CNTs加入量对铸态复合材料力学性能的影响规律,并用扫描电子显微镜观察了复合材料的拉伸断口形貌以及显微组织.结果表明:复合材料显微组织为等轴晶,包覆镍的CNTs主要分布在α-Mg共晶相内和晶界处,不仅起到细化晶粒的作用,而且还起到搭接晶粒和强化晶界的作用;复合材料的力学性能随CNTs加入量的增多呈现先增大后减小的趋势,当其质量分数为1%时,抗拉强度、显微硬度、伸长率同时达到最大,比AM60镁合金分别提高了46.23%,41.82%,74.52%,弹性模量在其质量分数为1.2%时达到最大.

Carbon nanotubes(CNTs) coated by Ni/AM60 magnesium alloy composite was fabricated by mechanical stirring casting technology.The effect of carbon nanotubes content on the mechanical properties of as-cast composites was studied.The microstructure and fractographs were observed and analyzed by using scanning electron microscopy.The results show that the microstructure of the composite was equiaxed grains and the CNTs coated by Ni mainly distributed on the eutectic phase and eutectic boundaries,which not only had the role of refining grains,but also played the role of lapping grains and strengthening grain boundaries.Mechanical properties of the composite first increased and then decreased as the CNTs addition increased when the mass fraction was 1%.The tensile strength,microhardness and elongation were maximized at the same time,increased 46.23%,41.82%,7452% respectively compared to the AM60 magnesium alloy.The elastic modulus was maximized when mass fraction was 1.2%.