7N01铝合金搅拌摩擦焊接头力学性能

Mechanical properties of 7N01 aluminum friction stir welding joint

研究了在不同焊接参数的条件下,7N01铝合金搅拌摩擦焊接头的力学性能.结果表明,在特定的旋转频率和前进速度匹配条件下,下压量在0.3～1.0 mm范围波动,7N01铝合金搅拌摩擦焊接头的抗拉强度均能够稳定在340 MPa以上,达到母材的80%左右.通过扫描电镜观察断口发现,搅拌摩擦焊接头断口以韧窝型为主,在低倍下部分断口呈现出明显的分层现象,两层间分界部分呈现出阶梯状形貌.接头硬度测试表明,后退侧的平均硬度略高于前进侧,这也与拉伸测试中接头普遍断于前进侧的现象吻合.

Mechanical properties of friction stir welded 7N01 aluminum joint under different welding parameters have been studied in this paper.The tensile test results showed that,with a certain rotational speed and welding speed,the FSW joints could keep at a high strength level of 340 MPa even the plunge depth varied from 0.3 to 1.0 mm.SEM was carried and the FSW joints exhibited mainly dimpled fracture surfaces.Hardness of the joints was also measured.The hardness in retreating side was a little higher than that of advancing side.This result corresponded well with the tensile test result.Fracture occurred at the advancing side in tensile test.