钛合金搅拌摩擦焊工艺参数对组织性能的影响

摘要

Effect of processing parameters on microstructural evolution are investigated by friction stir welding for the thickness of 2mmTi-6Al-4V alloy. The results show that the microstructures of joints are affected by processing parameters. The microstructure of joints is transformed fromαphase equiaxed ultra-ifned grains to fine α+β lamellar with increasing the rotation speed from 100r/min to 400r/min. The strength of joints exceeds 1000MPa with the elongation of 9.8%by varies of process-ing parameters. The mechanical properties of joints provide a higher strength with better plasticity deformation behavior.%采用不同工艺参数对2.0mm厚TC4钛合金板材进行搅拌摩擦对接焊，研究工艺参数对接头组织演变规律及其对接头性能的影响。结果表明：通过调整工艺参数，接头可得到不同状态的组织形式，从而影响接头的力学性能；随着转速从100r/min增加到400r/min，热输入量逐渐增大，接头内微观组织由完全的α相超细晶组织转变为完全的α+β片层状组织结构；在各工艺参数条件下，接头抗拉强度均超过1000MPa，最大延伸率可达到9.8%，在保证接头强度的同时具有较高的塑性变形能力。