固溶温度对GH4169合金锻件力学及焊接性能的影响

为了能同时满足某固溶态使用的GH4169合金航天锻件的力学和焊接性能的要求,研究了固溶温度对GH4169合金锻件硬度和拉伸性能的影响规律,并对相应固溶温度下锻件的同种和异种金属的焊接质量进行了表征分析。结果表明,固溶温度对合金的微观组织和力学性能均有显著影响,随着固溶温度的提高,晶界粗大相(主要为δ相)的回溶不断增加,合金的硬度及强度指标显著下降,伸长率显著提高。对经不同温度固溶处理的GH4169合金进行同种金属和异种金属(920 ℃固溶处理GH4169合金和固溶态0Cr18Ni9不锈钢)的焊接试验,其焊缝宏观、微观、X光检测均能满足使用要求,结合力学和焊接质量最终确定固溶态使用的GH4169合金锻件的最佳固溶温度为900~940 ℃。

Effect of solution treatment temperature on mechanical and welding properties of GH4169 alloy forging

In order to satisfy simultaneously the mechanical and welding properties of the aerospace-used forged GH4169 alloy parts in solution treated state, the effect of solution treatment temperature on hardness and tensile properties of the alloy forging was studied, and the qualities of homogeneous welding and dissimilar metal welding for solution treated GH4169 alloy and 0Cr18Ni9 stainless steel were characterized at corresponding solution treatment temperatures. The results show that the solution treatment temperature has significant impact on microstructure and mechanical properties of the GH4169 alloy, the dissolved degree of coarse second phases (δ phase mainly) increases and both the hardness and the tensile strength reduce significantly with the increase of solution treatment temperature, while the elongation increases significantly. The experiment results of both the homogeneous welding between GH4169 alloy solution treated at different temperatures and the dissimilar metal welding with the stainless steel 0Cr18Ni9 indicate that their macrostructure, microstructure and X-ray test results all satisfy the requirement for using. Considering both the mechanical properties and welding properties, the optimal range of solution treatment temperature of the GH4169 alloy forging used in solution treated state is 900-940 ℃.