激光冲击强化对AZ31和AZ80-T6镁合金显微组织及力学性能的影响  

Effect of laser shock processing on microstructures and mechanical properties of AZ31 and AZ80D-T6 magnesium alloys

作　　者：张青来[1] 邵伟[1] 张冰昕 吴铁丹 王荣[1] 

机构地区：[1]江苏大学材料科学与工程学院,镇江212013 [2]上海交通大学密西根学院,上海200240

出　　处：《中国有色金属学报》2015年第10期2680-2687,共8页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(51175231)

摘　　要：为了研究激光冲击强化(LSP)对镁合金力学性能的影响,采用电子万能拉伸机和显微硬度测试仪研究AZ31和AZ80D-T6镁合金拉伸应力-应变曲线和显微组织。结果表明:经LSP处理后,AZ80-T6和AZ31合金的抗拉强度分别增加4.6%和15.7%,其表层硬度分别增加22.7%和31.8%;AZ31合金激光冲击强化效果比AZ80D-T6合金的更加显著,激光冲击产生高幅残余压应力和高密度孪晶以及细小片层状、短棒状或动态析出β相,晶粒细化形成超细晶,并讨论预时效β析出相对镁合金激光冲击强化的影响和拉伸断口特征。In order to study the effect of laser shock processing （LSP） on mechanical properties of magnesium alloys, the tensile stress-strain curves and mierostructures of AZ31 and AZ80D-T6 magnesium alloys were investigated by electronic universal tensile machine and microhardness test. The results show that after LSP, the tensile strengths of AZ80-T6 and AZ31 alloys increase by 4.6% and 15.7%, the surface hardnesses increase by 22.7% and 31.8%, respectively. The strengthening effect of LSP on AZ31 is more significant than that on AZ80D-T6. The LSP generates high value residual compressive stress and high-density twins as well as the fine lamellar or short columnar or dynamic precipitation β phases. The grains are refined and the ultrafine grains are formed. The effect of pre-aged β precipitates on LSP strengthening effect and tensile fracture characteristics were discussed.

关 键 词：镁合金 激光冲击强化 应力-应变曲线 力学性能 显微组织 

分 类 号：TN249[电子电信—物理电子学] TG146.2[一般工业技术—材料科学与工程]