摘要
研究了5083铝合金搅拌摩擦焊(FSW)焊接接头组织与性能,采用金相显微镜观察焊接接头各区域的微观组织,并对接头显微硬度和力学性能进行了测定。结果表明,5083铝合金搅拌摩擦焊焊核组织为动态再结晶生成的细小组织,强化相均匀分布;热机影响区由于动态再结晶和焊接热循环的双重作用,组织变化较大,晶粒有一定程度的长大,强化相有所细化;热影响区仅仅受到热循环作用,使得晶粒粗化和强化相出现聚集现象。搅拌摩擦焊接接头中心硬度与母材基本相当,热机影响区和热影响区由于焊接热输入的原因,使得硬度有所降低。搅拌摩擦焊室温拉伸性能和冲击性能不低于母材的,其中拉伸试样均断裂于母材,焊核室温冲击值达到母材的1.5倍以上,热影响区冲击值与母材的相当。
Microstructure and mechanical properties of 5083 aluminum alloy friction stir welding（ FSW） joints were researched.The microstructure of each welding region was observed by optical microscopy,and the micro-hardness and mechanical properties were determined. The results show that the microstructure of weld nugget is tiny dynamic recrystallizatal grain,and strengthen phase distributed evenly. Because of the effect of dynamic recrystallization and the welding heat input,the mechanical heataffected zone changed greatly,and the grain grows a lot,while the strengthen phase refined. The heat-affected zone influenced by welding heat input only,so grains coarsen and the strengthen phases aggregate. The hardness of friction stir welded joint is almost equal to that of the base metal. Owing to the welding heat input,the hardness of TMAZ and HAZ decrease. The tensile and impact properties of FSW joints are not less than that of the base metal,which tensile specimens were broken in the base metal,and the impact of joints reached more than 1. 5 times of the base metal. The impact value of heat affected zone match to base metal considerably.
出处
《材料开发与应用》
CAS
2015年第5期25-30,共6页
Development and Application of Materials
基金
国家自然科学基金资助(U1404502)
