中国激光, 2014, 41 (3): 0303001, 网络出版: 2014-02-26  

Mg-9.8Li-2.9Al-Zn合金激光焊接接头组织与力学性能研究

Microstructure and Mechanical Property of Mg-9.8Li-2.9Al-Zn Alloy Laser Welded Joint
作者单位
北京工业大学激光工程研究院, 北京 100124
摘要
采用CO2激光焊接2 mm厚Mg-9.8Li-2.9Al-Zn合金,通过光学显微镜(OM)、扫描电镜(SEM)系统研究焊接接头成形、气孔裂纹缺陷、显微组织演变,并采用显微硬度测量和纵向拉伸测试焊接件的室温力学性能。结果表明,激光快速加热焊缝组织明显细化,α-Mg相增多且由母材的粗大组织转变为细针状组织,亚稳定的MgLi2Al相分解为稳定的AlLi相。焊缝的显微硬度(约105 HV)高于母材的显微硬度(约85 HV),对焊接件纵向拉伸断裂于母材,断裂后屈服强度Rp0.2为172 MPa,伸长率约为24%。
Abstract
The welding property of Mg-9.8Li-2.9Al-Zn alloy with the thickness of 2 mm using the CO2 laser is investigated. The joint forming, weld defects and structural evolution are studied with optical microscope (OM) and scanning electron microscope (SEM). The mechanical property of the weldment is tested using the microhardness and longitudinal tensile test at room temperature. The result indicates that the rapid cooling during the laser welding results in the fine microstructures with more α-Mg phase in the weld, compared with that in the base metal. The metastable phase MgLi2Al transforms into the stable phase AlLi. The weld microhardness (about 105 HV) is bigger than that of the base metal (about 85 HV). The longitudinal tensile test of the weldment shows the fractured location along the base metal with the reference yield strength of 172 MPa and the percentage elongation after fracture of about 24%.
参考文献

[1] M Avedesian, H Baker. ASM Specialty Handbook-Magnesium and Magnesium Alloys[M]. Ohio: ASM, 1999. 39.

[2] 张密林. 镁锂超轻合金[M]. 北京: 科学出版社, 2010. 270-290.

    Zhang Milin. Magnesium-Lithium Superlight Alloys[M]. Beijing: Science Press, 2010. 270-290.

[3] 董长富, 刘黎明, 赵旭. 变形镁合金填丝TIG焊接工艺及组织性能分析[J]. 焊接学报, 2005, 26(2): 33-36.

    Dong Changfu, Liu Liming, Zhao Xu. Welding technology and microstructure of tungsten inert-gas welded magnesium[J]. Transactions of the China Welding Institution, 2005, 26(2): 33-36.

[4] A Munitz, C Cotler, A Stern, et al.. Mechanical properties and microstructure of gas tungsten arc welded magnesium AZ91D plates[J]. Mater Sci Eng A, 2001, 302(1): 68-73.

[5] G Atkins, M Marya, D Olson, et al.. Magnesium-lithium alloy weldability: a microstructural characterizaiton[C]. Magnesium Technology, In Proceedings of TMS 2004. 37-41.

[6] Liu Xuhe, Gu Shihai, Wu Ruizhi, et al.. Microstructure and mechanical properties of Mg-Li alloy after TIG welding[J]. Trans Nonferrous Met Soc China, 2011, 21(3): 477-481.

[7] 全亚杰. 镁合金激光焊的研究现状及发展趋势[J]. 激光与光电子学进展, 2012, 49(5): 050001.

    Quan Yajie. Research status and development trends of laser welding of magnesium alloy[J]. Laser & Optoelectronics Progress, 2012, 49(5): 050001.

[8] 张婧, 单际国, 温鹏, 等. 压铸镁合金激光焊气孔形成规律及原因[J]. 中国激光, 2011, 38(6): 0603006.

    Zhang Jing, Shan Jiguo, Wen Peng, et al.. Formation regularity of pores during laser welding of die-cast magnesium alloys and its mechanism[J]. Chinese J Lasers, 2011, 38(6): 0603006.

[9] 檀财旺, 李俐群, 陈彦宾, 等. AZ31B镁合金的光纤激光与CO2激光焊接特性[J]. 中国激光, 2011, 38(6): 0603015.

    Tan Caiwang, Li Liqun, Chen Yanbin, et al.. Characteristics of fiber laser and CO2 laser welding of AZ31B magnesium alloys[J]. Chinese J Lasers, 2011, 38(6): 0603015.

[10] A Belhadj, J E Masse, Laurent Barrallier, et al.. CO2 laser beam welding of AM60 magnesium-based alloy[J]. J Laser Appl, 2010, 22(2): 56-61.

[11] Ma Leijuan, Hao Hai, Dong Hanwei, et al.. Effects of electromagnetic field on structure and heat treatment behavior of Mg-Li-Al alloys[J]. Trans Nonferrous Met Soc China, 2008, 18(s1): s96-s100.

[12] Chiu Chuihung, Wang Jianyih, Wu Horngyu. Microstructural characterization of a Mg-9%Li-1%Zn alloy[J]. Materials Transactions, 2006, 47(4): 966-972.

[13] S M Chowdhury, D L Chen, S D Bhole, et al.. Microstructure and mechanical properties of fiber-laser-welded and diode-laser-welded AZ31 magnesium alloy[J]. Metallurgical and Materials Transactions A, 2011, 42(7): 1974-1989.

[14] 朱昌盛, 石可伟, 王智平, 等. 相场法模拟潜热的释放对多元合金凝固过程的影响[J]. 兰州理工大学学报, 2008, 34(2): 6-10.

    Zhu Changsheng, Shi Kewei, Wang Zhiping, et al.. Simulation of effect of latent heat release on the solidification of multicomponent alloys with phase-field method[J]. J Lanzhou University of Technology, 2008, 34(2): 6-10.

吕俊霞, 杨武雄, 吴世凯, 肖荣诗. Mg-9.8Li-2.9Al-Zn合金激光焊接接头组织与力学性能研究[J]. 中国激光, 2014, 41(3): 0303001. Lü Junxia, Yang Wuxiong, Wu Shikai, Xiao Rongshi. Microstructure and Mechanical Property of Mg-9.8Li-2.9Al-Zn Alloy Laser Welded Joint[J]. Chinese Journal of Lasers, 2014, 41(3): 0303001.

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