激光表面熔凝对AZ31镁合金显微组织及性能的影响  

Effect of Laser Surface Melting on the Microstructure and Properties of AZ31 Magnesium Alloy

作　　者：周猛兵 张超 陈高詹 车垒辰 伍佳瑶 Zhou Mengbing;Zhang Chao;Chen Gaozhan;Che Leichen;Wu Jiayao(Institute of Nuclear Fuel Elements and Materials,China Nuclear Power Research and Design Institute,Chengdu 610213,Sichuan,China)

机构地区：[1]中国核动力研究设计院,核燃料元件及材料研究所,四川成都610213

出　　处：《应用激光》2025年第2期60-69,共10页Applied Laser

摘　　要：利用激光在纯氩气气氛条件下对AZ31镁合金表面进行激光熔凝处理,并通过光学显微镜、扫描电镜、能谱分析仪等研究低功率激光表面熔凝制备的超薄AZ31镁合金表面熔凝层的组织、结构以及耐腐蚀性能。结果显示,激光熔凝层组织致密,熔凝层的晶粒尺寸小于20μm,表面显微硬度由51~58 HV增加至74~78 HV;经激光熔凝处理后,熔凝层组织中Al元素的固溶度增加,同时激光熔凝过程存在凝固裂纹敏感性;镁合金经激光熔凝处理后,其腐蚀电位比基体组织提高0.285 V,而腐蚀电流密度相比基体镁合金减小了1个数量级,耐腐蚀性能得到一定程度的改善。The surface of AZ31 magnesium alloy was treated by laser melting under pure argon atmosphere,and the microstructure,structure,and corrosion resistance of the ultra-thin AZ31 magnesium alloy surface melting layer prepared by low-power laser surface melting were studied through optical microscopy,scanning electron microscopy,and energy spectrum analyzer.The results indicated that the laser-melted layer exhibited a dense microstructure with grain sizes smaller than 20μm.The surface microhardness increased from 5158 HV to 7478 HV after treatment.After laser melting treatment,the solid solubility of Al element in the microstructure of the melting layer increases,and there is a sensitivity to solidification cracks during the laser melting process.After laser melting and solidification treatment,the corrosion potential of magnesium alloy increased by 0.285 V compared to the matrix structure,and the corrosion current density decreased by one order of magnitude compared to the matrix magnesium alloy,resulting in a certain degree of improvement in corrosion resistance.

关 键 词：激光熔凝 AZ31镁合金 微观组织 缺陷 腐蚀性能 

分 类 号：TG174[金属学及工艺—金属表面处理]