2195铝锂合金搅拌摩擦焊接头组织及性能

Microstructures and Properties of Friction-Stir Welded Joint of 2195 Al-Li Alloy

为了研究搅拌摩擦焊（FSW）对2195铝锂合金组织及性能的影响,对5mm薄板进行了不同工艺参数的搅拌摩擦焊接。显微组织分析及力学测试结果表明：合金经FSW后,接头组织由焊核区、热机影响区、热影响区三个明显不同的区域组成。当焊速不变,搅拌头转速ω在700～1300r/min之间变化时,接头抗拉强度随转速ω增大而降低;搅拌头转速不变,焊速υ在60～140mm.min-1之间变化时,接头抗拉强度随焊速υ增大而提高。当υ=140mm.min-1,ω=1000r/min时,焊接接头强度系数达到73%。焊后接头显微硬度发生了较大程度的软化。

In order to determine the effects of friction stir welding on both microstructures and properties of 2195 Al-Li alloy,the friction stir welding experiments with different welding parameters were carried on this alloy.Microstructures and mechanical properties were analyzed.The results indicate that the welded joint is composed of three distinctive zones： welded nugget zone（WNZ）,thermo-mechanically affected zone（TMAZ）,heat affected zone（HAZ）.When welding speed υ=100 mm·min-1,the rotating speed ω is between 700r/min and 1300r/min,the tensile strength of the welded joints decreases with the rotating speed improving;when rotating speed ω= 1000r/min,the welding speed υ is between 60mm·min-1 and 140mm·min-1,the tensile strength of the welded joints raises with the welding speed increasing.Joint strength coefficient is 73% at ω= 1000rpm,υ=140mm·min-1.The hardness of the welded joint decreases obviously.