摘要
镁合金焊接接头的微观组织对其力学性能有显著影响,限制其更广泛应用。受大自然生物结构所表现的优异力学性能的启发,利用激光重熔技术在镁合金钨极惰性气体保护焊(TIG焊)焊接接头表面制备了与生物体表类似的“软硬”交替结构来改善其力学性能。采用激光共聚焦显微镜、扫描电镜、能谱仪、硬度计、万能拉伸试验机、有限元分析等研究了不同试样的微观组织和力学性能。结果表明:激光仿生处理后,处理区形成了细小的等轴晶粒并且显微硬度明显增加,仿生试样的强度和延展性同时提高。结合有限元分析结果可知,仿生结构对力学性能的有益影响可归因于微观组织的变化和“软硬”交替结构带来的应力传递和重分布。
The microstructure of magnesium alloy welded joints has a significant effect on its mechanical properties,which affects its application range.Inspired by the excellent mechanical properties of natural biological structures,a“soft-hard”alternating structure similar to the biological surface was prepared on the surface of magnesium alloy tungsten inert gas(TIG)welding joint by laser remelting technology to improve its mechanical properties.The microstructure and mechanical properties of different samples were studied by means of laser confocal microscope,scanning electron microscopy,energy dispersive spectrometer,hardness tester,universal tensile testing machine and finite element analysis.The results show that after laser bionic treatment,fine equiaxed grains are formed in the treatment area,the microhardness is significantly increased,and the strength and ductility of the bionic sample are simultaneously improved.Combined with the results of finite element analysis,it can be seen that the beneficial effect of the bionic structure on mechanical properties can be attributed to the change of microstructure and the stress transfer and redistribution brought by the“soft-hard”alternating structure.
作者
时海芳
张正强
姜永恒
孟超
SHI Hai-fang;ZHANG Zheng-qiang;JIANG Yong-heng;MENG Chao(College of Materials Science and Engineering,Liaoning Technical University,Fuxin 123000,China)
出处
《材料热处理学报》
CAS
CSCD
北大核心
2023年第2期179-188,共10页
Transactions of Materials and Heat Treatment
基金
国家自然科学基金(51805235)。
