固溶温度对改型In617合金组织和性能的影响

Effect of solution treatment temperature on microstructure and properties of modified In617 alloy

通过光学显微镜(OM)、扫描电镜(SEM)表征、EDS分析以及力学性能测试等方法研究了固溶温度对改型Inconel617(In617)合金组织和性能的影响。结果表明,改型In617合金在950~1200℃固溶2.5 h,平均晶粒尺寸从18μm增长至183μm;并建立了改型In617合金在950~1200℃固溶处理过程中的晶粒长大动力学模型。当固溶温度为1000℃时,晶界处M_(23)C_(6)碳化物回溶;超过1100℃固溶时,M_(6)C碳化物也基本回溶完毕,合金中仅存大尺寸MC型碳化物。随着固溶温度升高,混晶现象发生,合金高温强度逐渐降低,主要归因于碳化物的逐步回溶。其中在1050℃固溶时,由于晶界碳化物没有回溶完毕,所以此时改型In617合金的强度下降幅度不高,而当固溶温度达到1200℃时,晶界处碳化物消失,晶粒已经长大,导致合金强度大幅降低。

Effects of solution treatment temperature on microstructure and properties of modified In617 alloy were studied by means of OM and SEM characterization,EDS analysis and mechanical properties test.The results show that the average grain size of the alloy increases from 18μm to 183μm after solution treatment at 950-1200℃for 2.5 h.The kinetic model of grain growth of the alloy during solution treatment at 950-1200℃is established.When the solution treatment temperature is 1000℃,the M_(23)C_(6)carbide at grain boundary is redissolved.When the solution treatment temperature exceeds 1100℃,the dissolution of M_(6)C carbides is basically completed,and only largesize MC carbides exist in the alloy.When the solid solution treatment temperature rises,the mixed grain phenomenon occurs,and the high temperature strength of the alloy gradually decreases,which is mainly due to the gradual redissolution of the carbides.When the solid solution treatment temperature is 1050℃,the strength of the alloy decreases a little due to insufficient dissolution of the carbides at grain boundary.When the solution treatment temperature increases to 1200℃,the strength of the alloy is greatly reduced due to that the carbides at grain boundary disappear and the grain growth.