摘要: |
采用钨极氩弧焊对5mm厚的LA103W镁锂合金板材进行焊接,研究LA103W镁锂合金的焊接质量、显微组织与力学性能。结果表明,焊接接头表面成型良好,焊缝中无超标气孔、裂纹等缺陷;接头的组织由α-Mg相和β-Li相组成,母材区和热影响区的β-Li相晶粒为等轴状,焊缝区和熔合区中含大量颗粒状和细针状的α-Mg相,熔合区中的α-Mg相均匀分布在β-Li相中,熔合良好,不易发生断裂。焊接接头的抗拉强度和延伸率均略低于母材,分别为母材的92.1%和90%。焊接接头的断裂方式为韧性-解理混合断裂,断裂在母材区。 |
关键词: LA103W;镁锂合金;显微组织;力学性能 |
基金项目: |
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Research on the Microstructure and Mechanical Properties ofTIG Welded Joint of LA103W Mg-Li Alloy |
Xia Congcong Ma Licai Lu Chuanyang Wang Feng Tang Jiaqi
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Beijing Xinfeng Aerospace Equipment Co., Ltd., Beijing 100080
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Abstract: |
Using tungsten inert gas welding to weld LA103W magnesium lithium alloy plate with thickness of 5mm, the welding quality, microstructure, and mechanical properties of LA103W alloy were studied. The results show that surface quality of welded joint was good, and no obvious pores and cracks were found in the weld. The microstructure of welded joint consisted of α-Mg phase and β-Li phase. The β-Li phase grain in the base metal zone and the heat-affected zone was equiaxed, and a large number of fine needle and granular α-Mg phase was found in the weld zone and fusion zone. The α-Mg phase of the fusion zone is evenly distributed in the β-Li phase, and the fusion is good. The fusion zone is not prone to fracture. The tensile strength and elongation of welded joint were slightly lower than those of the base metal, which respectively reach 92.1% and 90% of the base metal. The fracture mode of welded joint was ductile-cleavage fracture, and the tensile fracture was located at the base metal zone. |
Key words: LA103W;Mg-Li alloy;microstructure;mechanical properties |