【摘要】 研究不同固溶处理温度和时效处理温度对SRR99镍基单晶高温合金的微观组织和持久性能的影响。利用扫描电镜和光学金相显微镜对显微组织进行表征和分析,利用GWT304常载拉伸蠕变试验机测试其持久性能。结果表明:随着一次时效温度的提高,二次γ′相尺寸逐渐增大,γ′相体积分数先增加后降低;随着固溶温度的提高,合金中残余共晶含量减少,偏析逐渐降低,在1050℃/150MPa条件下,合金的持久寿命呈现先增加后降低的趋势。更多还原

【Abstract】 The effects of solution and aging heat treatment temperatures on the microstructures and stress rupture properties in SRR99 single crystal Ni-base superalloy were investigated.The microstructures were examined by SEM and OM.Creep tests were carried out at a GWT304 constant load high temperature creep-testing machine,the loading condition being 1010℃/248MPa.The results showed that,with the enhancing of primary aging temperature,the size of secondary γ′ phase increased and the volume fraction of γ′ phase increased firstly with subsequent decreasing.The higher the solution treatment temperature was,the lower the amount of remained eutectic γ′ and the segregation of alloy elements were.The stress rupture lives of SRR99 single crystal superalloy increased firstly and then decreased with the increasing of solid solution treatment temperature.更多还原