Mg-Gd-Y-Zr镁合金高速激光熔覆Al-Si涂层的组织与性能  

Microstructure and properties of high speed laser clad Al-Si coating on Mg-Gd-Y-Zr magnesium alloy

作　　者：杨胶溪[1] 黄凯 武飞宇 孙宏波 阳代军 李曙光 葛学元 王淼辉[3,4] Yang Jiaoxi;Huang Kai;Wu Feiyu;Sun Hongbo;Yang Daijun;Li Shuguang;Ge Xueyuan;Wang Miaohui(Institute of Laser Engineering,Faculty of Material and Manufacturing,Beijing University of Technology,Beijing 100124,China;Capital Aerospace Machinery Co.,Ltd.,Beijing 100076,China;Beijing National Innovation Institute of Lightweight Ltd.,Beijing 100083,China;State Key Laboratory for Advanced Forming Technology and Equipment,China Academy of Machinery and Technology,Beijing 100083,China)

机构地区：[1]北京工业大学材料与制造学部激光工程研究院,北京100124 [2]首都航天机械有限公司,北京100076 [3]北京机科国创轻量化科学研究院有限公司,北京100083 [4]中国机械科学研究总院先进成形技术与装备国家重点实验室,北京100083

出　　处：《金属热处理》2023年第1期217-223,共7页Heat Treatment of Metals

基　　金：国家自然科学基金(52075011);先进成形技术与装备国家重点实验室开放基金(SKL202003)。

摘　　要：采用高速激光熔覆技术在Mg-Gd-Y-Zr镁合金表面制备Al-Si涂层。通过光学显微镜(OM)、X射线衍射仪(XRD)、扫描电镜(SEM)以及电化学分析测试、摩擦磨损测试对熔覆层的微观组织及性能进行表征,研究了基体与Al-Si涂层的冶金机理以及耐磨耐蚀能力。结果表明,熔覆层组织包括树枝状α-Mg固溶体、不规则块状Mg_(2)Si、α-Mg+Al_(12)Mg_(17)共晶以及花瓣状组织Al_(3)Mg_(2)。由于细晶强化和第二相强化等原因,Al-Si涂层的硬度达到160 HV0.1。此外,与镁合金基体相比,Al-Si涂层的耐腐蚀性能显著提高,自腐蚀电位相比基体提高约200 mV,自腐蚀电流密度降低2个数量级,抗磨损效果提高30.7%,因此Al-Si涂层有望成为稀土镁合金更有前景的耐磨耐蚀防护涂层。Microstructure and properties of Al-Si coating prepared on the surface of Mg-Gd-Y-Zr magnesium alloy by high-speed laser cladding process were characterized by means of optical microscope(OM),X-ray diffractometer(XRD),scanning electron microscope(SEM)and electrochemical test and wear test,and the metallurgical mechanism and wear and corrosion resistance of the substrate and Al-Si coating were analyzed.The results show than the microstructure of clad coating consists of dendriticα-Mg solid solution,irregular massive Mg_(2)Si,α-Mg+Mg_(17)Al_(12)eutectic and petal-like Mg_(2)Al_(3).Due to grain refinement strengthening and secondary phase strengthening,the hardness of the Al-Si coating reaches 160 HV0.1.In addition,compared with the magnesium alloy substrate,the corrosion resistance of the Al-Si coating is significantly improved,the self-corrosion potential is increased by about 200 mV,the self-corrosion current density is reduced by 2 orders of magnitude,and the anti-wear effect is increased by 30.7%,which indicate that the Al-Si coating is expected to become a more promising wear and corrosion resistant protective coatings for rare earth magnesium alloys.

关 键 词：稀土镁合金 激光熔覆 AL-SI涂层 显微组织 耐腐蚀性 耐磨性能 

分 类 号：TG174.4[金属学及工艺—金属表面处理]