热挤压和脉冲电流对AZ91镁合金及其复合材料显微组织和力学性能的影响  

Effect of Hot Extrusion and Pulse Current on the Microstructure and Mechanical Properties of AZ91 Magnesium Alloy and Its Composites

作　　者：武红飞 胡文鑫 马少博[1,2] WU Hongfei;HU Wenxin;MA Shaobo(National Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization,Baotou 014030,China;Baotou Research Institute of Rare Earths,Baotou 014030,China)

机构地区：[1]白云鄂博稀土资源研究与综合利用全国重点实验室,内蒙古包头014030 [2]包头稀土研究院,内蒙古包头014030

出　　处：《铸造技术》2024年第2期157-162,共6页Foundry Technology

基　　金：国家重点研发计划(2021YFB3501001);白云鄂博稀土资源研究与综合利用全国重点实验室项目(2022Z2439)。

摘　　要：为探究SiC_(p)对AZ91镁合金在电脉冲处理过程中组织和性能演变规律的影响,通过在AZ91合金中添加1%(体积分数)微米级SiC_(p)制备了SiC_(p)/AZ91复合材料,联合低温正挤压和电脉冲处理对AZ91合金和SiC_(p)/AZ91复合材料的组织进行细化,利用光学显微镜分析显微组织的演化,测试合金和复合材料的室温力学性能。结果表明,和AZ91合金相比,添加了增强相颗粒后的复合材料挤压之后具有更高的位错密度和形变储存能,从而促进电脉冲处理时的静态再结晶过程。电脉冲处理后的AZ91合金及复合材料的屈服强度和抗拉强度分别为320、450 MPa和380、454 MPa。由于SiC_(p)与镁基体界面处应力集中而形成的微裂纹,导致复合材料抗拉强度增幅较小。To investigate the effect of SiC_(p) on the evolution of the microstructure and properties of an AZ91 magnesium alloy during electric pulse treatment(EPT),a SiC_(p)/AZ91 composite was prepared by adding 1%(volume fraction)micron SiC_(p) to an AZ91 magnesium alloy.The microstructure of the AZ91 alloy and SiC_(p)/AZ91 composite was refined by low temperature extrusion and electric pulse treatment.The microstructure evolution was analysed by optical microscope.The mechanical properties of the alloys and composites were tested at room temperature.The results show that the composite with reinforced phase particles has a greater dislocation density and greater deformation storage energy after extrusion compared with AZ91 alloy,thus promoting static recrystallization during electric pulse treatment.The yield strength and tensile strength of the AZ91 alloy and composite after pulse treatment are 320 and 450 MPa,and 380 and 454 MPa,respectively.Due to the stress concentration at the interface between the SiC_(p) and the magnesium matrix,the tensile strength of the composite lightly increases.

关 键 词：镁基复合材料 热挤压 电脉冲处理 静态再结晶 力学性能 

分 类 号：TB331[一般工业技术—材料科学与工程] TG113.25[金属学及工艺—物理冶金]