摘要
利用搅拌摩擦焊技术成功制备了304/430异种不锈钢接头,分析了不同旋转速度下的焊缝表面形貌、接头组织结构和力学性能,并对接头的断裂行为进行了研究。结果表明:搅拌摩擦焊接过程中,提高旋转速度可以增加热输入,增强材料的流动性。旋转速度800 r/min,焊接速度30 mm/min时,焊缝成形良好,无沟槽和飞边,搅拌区奥氏体不锈钢和铁素体不锈钢混合均匀,紊流清晰,实现良好的冶金结合;接头的抗拉强度为443.8 MPa,约为430铁素体不锈钢抗拉强度的80%;试样拉伸断裂在热力影响区,属于延性断裂。
304/430 dissimilar stainless steel joints were successfully fabricated by using friction stir welding. The weld appearance, the structure and mechanical properties of the welded joints under different rotational speeds were analyzed, and the fracture behavior of the joint was studied. The results show that during the friction stir welding, increasing rotational speed can increase the heat input and enhance the material flowability. When the rotational speed is 800 r/min and the welding speed is 30 mm/min, the weld forming is good, the weld has no groove and fly edge, and austenitic stainless steel and ferritic stainless steel are mixed evenly in the stir zone, with clear turbulence and good metallurgical bonding. The tensile strength of the joint is 443.8 MPa, about 80% of that of 430 ferrite stainless steel. The tensile fracture of the specimen is in heat-mechanical affected zone,which is ductile fracture.
引文
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