搅拌摩擦处理对镁合金电弧增材修复层缺陷调控  

Control of Defects in Mg Alloy Arc Additive Repair Layer by Friction Stir Treatment

作　　者：李建伟 何智[2,3] 龙建周 殷凤良 高红月 赵玥 郭晓琳 王志敏[2] 刘玉平[2] 张铁军[2] 郭斌[1] LI Jianwei;HE Zhi;LONG Jianzhou;YIN Fengliang;GAO Hongyue;ZHAO Yue;GUO Xiaolin;WANG Zhimin;LIU Yuping;ZHANG Tiejun;GUO Bin(School of Materials Science and Engineering,Harbin Institute of Technology,Harbin 150001;Beijing Hangxing Machinery Manufacture Limited Corporation,Beijing 100013;College of Mechanical Engineering and Applied Electronics Technology,Beijing University of Technology,Beijing 100124;School of Mechanical Engineering,Tsinghua University,Beijing 100084)

机构地区：[1]哈尔滨工业大学材料科学与工程学院,哈尔滨150001 [2]北京航星机器制造有限公司,北京100013 [3]北京工业大学机械工程及应用电子技术学院,北京100124 [4]清华大学机械工程学院,北京100084

出　　处：《机械工程学报》2022年第4期55-61,共7页Journal of Mechanical Engineering

基　　金：国家自然科学基金资助项目(51775556)。

摘　　要：镁合金电弧增材冷金属过渡焊(Cold metal transition, CMT)电弧增材过程中存在导热快、结晶不规则等问题,易在搭接处形成明显孔洞缺陷,且零件表面粗糙,研究修复层缺陷调控对镁合金增材制造修复的发展和实际应用具有重要意义。研究表明,镁合金CMT快速增材制造实现了多焊道的搭接,并获得细小的晶粒(约10.5μm),平均显微硬度达0.89 GPa,具备较高的力学性能;经过搅拌摩擦处理,不仅改善了表面质量,还消除了焊道搭接与基板的界面处孔洞,晶粒得到进一步细化(约9.7μm),降低材料服役过程中的断裂风险。重点验证了镁合金电弧熔覆与搅拌摩擦处理复合制造的可行性,为高性能镁合金增材制造方法提供了新的思路。Magnesium alloy arc additive has fast thermal conductivity and irregular crystallization in the process of cold metal transition welding(CMT) arc additive, and easily forms obvious holes at weld seam joints and rough surfaces of the formed parts. The research on defect control of repair layer is of great significance to the development and practical application of magnesium alloy additive manufacturing repair. The research results show that CMT rapid additive remanufacturing of magnesium alloy has realized lap joint of multi-passes, reproduces the magnesium alloy with fine grain(~10.5 μm) and the average microhardness is up to 0.89GPa with high mechanical properties. After friction stir treatment, not only the surface quality is improved, but also the holes at the interface between weld pass laps and substrates are eliminated, and the grain is further refined(~9.7 μm), thus reducing the risk of fracture during service. The feasibility is emphatically verified the composite manufacturing of magnesium alloy arc cladding and friction stir processing, and a new idea for high-performance magnesium alloy additive manufacturing method is provided.

关 键 词：镁合金 冷金属过渡焊 搅拌摩擦处理 微观组织 显微硬度 

分 类 号：TG156[金属学及工艺—热处理]