离焦量对ZK60镁合金激光表面熔凝组织及性能的影响  

Effect of Defocusing Amount on Microstructure and Properties of LaserSurface Melting of ZK60 Magnesium Alloy

作　　者：张玺 韩峰[1,2] 赵柯 武冰冰 闫基森 解芳[1,2] ZHANG Xi;HAN Feng;ZHAO Ke;WU Bingbing;YAN Jisen;XIE Fang(Engineering Research Center of Additive Manufacturing Aeronautical Materials of Henan Province,Nanyang Institute of Technology,Nanyang 473004,China;Nanyang Key Laboratory of Additive Manufacturing Technology and Equipment,Nanyang Institute of Technology,Nanyang 473004,China)

机构地区：[1]南阳理工学院河南省增材制造航空材料工程研究中心,河南南阳473004 [2]南阳理工学院南阳市增材制造技术与装备重点实验室,河南南阳473004

出　　处：《有色金属工程》2023年第8期56-61,共6页Nonferrous Metals Engineering

基　　金：国家自然科学基金资助项目(51605230);河南省重点研发与推广专项(科技攻关)(222102240002,232102221022);南阳理工学院交叉科学研究项目(520064)。

摘　　要：为改善镁合金的耐蚀性,通过激光表面熔凝工艺在ZK60镁合金表面制备熔凝层。采用光学显微镜(OM)、X射线衍射仪(XRD)、显微维氏硬度计、电化学工作站分析了熔凝层的组织结构、表面形貌、显微硬度和耐蚀性。结果表明,激光表面熔凝处理可极大程度细化镁合金晶粒,熔凝层的厚度和粗糙度随激光离焦量的增大而减小,熔凝层由细小等轴晶和柱状晶组成,相组成主要为α-Mg相和MgZn2相。当离焦量为5 mm时,镁合金熔凝层的表面形貌和耐蚀性达到最佳,与未处理镁合金相比,熔凝层的显微硬度提高约36.1%,腐蚀电位向正向移动约0.097 V。In order to improve the corrosion resistance of magnesium alloy,laser surface melted layer was prepared on the surface of ZK60 magnesium alloy.The microstructure,surface morphology,microhardness and corrosion resistance of the melted layer were analyzed by Optical Microscope(OM),X-Ray Diffractometer(XRD),micro-Vickers hardness tester and electrochemical workstation.The results show that laser surface melting can refine magnesium alloy grains to a great extent,and the thickness and roughness of the melted layer decrease with the increase of laser defocusing amount.The melted layer is composed of fine equiaxed crystals and columnar crystals,and the phase composition is mainlyα-Mg phase and MgZn 2 phase.when the defocusing amount is 5 mm,the surface morphology and corrosion resistance of the molten layer of magnesium alloy reach the best.Compared with untreated magnesium alloy,the microhardness of molten layer increases by 36.1%,and the corrosion potential moves forward by 0.097 V.

关 键 词：ZK60镁合金 激光表面熔凝 离焦量 显微硬度 耐蚀性 

分 类 号：TG178[金属学及工艺—金属表面处理]