摘要
Double-V butt TIG welding process was performed on two plates of AA6061-T6 using ER5356 filler. The microstructure,mechanical and nanomechanical properties of the joint were evaluated in as-welded and after post weld heat treatment (PWHT) usingXRD, FESEM, EBSD, nanoindentation and tensile tests. The results show that PWHT led to microstructural recovery of the heataffected zone (HAZ) in addition to the appearance of β-phase (Al3Mg2) at the grain boundaries of weld zone. The hardness (Hnano) inall zones increased after PWHT while the elastic modulus (Enano) was improved from 69.93 GPa to 81 GPa in weld area. All resultsindicate that PWHT has created a homogenous microstructure in the weld zone in addition to outstanding improvement inmechanical properties for the weld zone which surpass the base metal.
采用ER5356焊料对AA6061-T6合金板材进行双V坡口气体保护钨极焊接。采用XRD、FESEM、EBSD、纳米压痕和拉伸测试研究焊接后及后续焊缝热处理后焊接接头的显微组织、力学性能和纳米力学性能。结果表明,后续焊缝热处理可使热影响区的显微组织恢复,并在焊缝区的晶界上形成β相(Al_3Mg_2)。经后续焊缝热处理后,所有区域的硬度均增加,而焊缝区的弹性模量从69.93 GPa增加至81 GPa。经后续焊缝热处理后,焊接区的显微组织均匀,与基体合金相比,力学性能得到提高。
基金
the financial support for this study from the Malaysian Ministry of Higher Education(MOHE) through the Fundamental Research Grant Scheme and Exploratory Research Grant Scheme