Analysis of Microstructure and Shear Fracture of Be Laser Welding Joint Using AlSi Alloy as Transition Material

作者：Li Yubin^*; Meng Daqiao; Liu Kezhao; Xie Zhiqiang; He Jiangjun

来源：Rare Metal Materials and Engineering, 2010, 39(5): 878-882.

• beryllium
• AlSi alloy
• laser welding
• microstructure
• shear fracture morphology

With AlSi alloy as transition material, beryllium and beryllium was welded by laser. The microstructure and performance of the welding joint was researched by means of scanning electron microscope (SEM), electron probe microanalysis (EPMA) and nano-indentation apparatus. The results indicate that the microstructure of the fusion zone and the weld zone for the Be laser welding joint was composed of compound phase of Be and AlSi alloy, and the width of fusion zone was about 10 mu m. The shear strength of the welding joint was similar to 283 MPa and the shear fracture mechanism is quasi-cleavage feature. The welding joint was ruptured mostly in the weld zone. The characteristic of shear fracture was quasi-cleavage with local ductile dimples. Brittle rupture for Be laser welding joint was attributed to micro-crack induced by welding thermal stress in fusion zone, intermetallic compound and gas porosity formed in the weld zone.

• 出版日期2010-5
• 单位中国工程物理研究院