论文部分内容阅读
通过搅拌铸造工艺制备出SiCP体积分数分别为2%、5%、10%和15%的4种5μm SiCP/镁合金(AZ91)复合材料。对5μm SiCP/AZ91进行了固溶、锻造和热挤压。通过与AZ91对比,研究了SiCP对AZ91基体热变形后显微组织和力学性能的影响规律。结果表明:SiCP/AZ91热变形后的晶粒尺寸取决于SiCP的体积分数。SiCP的体积分数由0%增加到10%时,SiCP/AZ91热变形后的平均晶粒尺寸减小;当SiCP颗粒继续增加到体积分数为15%时,平均晶粒尺寸反而增大。SiCP的加入能显著提高AZ91的屈服强度和弹性模量,并随颗粒体积分数的增加而增大。SiCP对AZ91基体的强化作用主要源于位错强化、细晶强化和载荷传递作用,其中,细晶强化对屈服强度的贡献最大。
Four kinds of 5μm SiCP / magnesium alloy (AZ91) composites with SiCP volume fraction of 2%, 5%, 10% and 15% were prepared by a stirring casting process. 5μm SiCP / AZ91 solution, forging and hot extrusion. By comparing with AZ91, the influence of SiCP on the microstructure and mechanical properties of AZ91 matrix was investigated. The results show that the grain size of SiCP / AZ91 after thermal deformation depends on the volume fraction of SiCP. When the volume fraction of SiCP increases from 0% to 10%, the average grain size decreases after SiCP / AZ91 thermal deformation. When the volume fraction of SiCP increases to 15%, the average grain size increases. The addition of SiCP can significantly improve the yield strength and elastic modulus of AZ91, and increase with the increase of particle volume fraction. The strengthening effect of SiCP on AZ91 matrix is mainly attributed to dislocation strengthening, fine grain strengthening and load transfer, among which the fine grain strengthening has the largest contribution to yield strength.