热处理工艺对TA15线性摩擦焊接头组织和力学性能的影响

Effect of Heat Treatment Process on Microstructure and Mechanical Property of TA15 Linear Friction Welding Joint

针对TA15钛合金线性摩擦焊接头,研究了不同热处理工艺对接头组织和力学性能的影响。研究结果表明:热处理过程中,针状亚稳态组织转变为片层α相+保留β相,并且随着热处理温度升高,片层结构逐渐增大。力学性能试验表明,接头拉伸断裂位置均在母材处,热处理后的焊接接头抗拉强度和屈服强度均高于焊态,且疲劳性能和冲击性能得到改善。为保证TA15钛合金线性摩擦焊接头获得较高的综合性能,热处理温度不应高于750℃。

The effect of heat treatment process on the microstructure and mechanical properties of TA15 linear friction welding （LFW） joint is investigated in this paper. The results show that the microstructure of needle-like metastability transforms to the lamellar α phase and β phase during the heat treatment process. As the temperature of heat treatment process increases, the lamella of the microstructure increases. The fracture positions of the tensile samples are all presented on the base metal. The mechanical properties, named the tensile strength, yield strength, are better than the base metal after heat treatment process. And the fatigue strength and impact properties increase after this process. In order to obtain higher synthetical performance of the weld joint, the temperature of the heat treatment process should not exceed 750℃.