(西北工业大学 凝固技术国家重点实验室，西安 710072)
摘 要: 对具有不同枝晶间距的CMSX-2单晶高温合金的凝固组织特征及其对热处理组 织和持久性能的影响进行了研究。考察了不同温度下不同枝晶间距组织的固溶情况及热处理后的组织均匀性，测试了持久性能。结果表明：随着凝固组织的细化，合金的组织均匀性得到提高，从而有效提高了合金的固溶温度，增大了热处理均匀化效果；CMSX-2合金铸态超细组织单晶的持久寿命是粗枝晶单晶的1.45倍，热处理态超细枝晶单晶的持久寿命是粗枝晶 单晶的1.85倍。单晶高温合金组织超细化是显著提高合金高温力学性能的有效手段。
关键字: 单晶高温合金；定向凝固；持久性能；热处理组织；组织细化
structures and mechanical properties in
single crystal superalloy
（State Key Laboratory of Solidification Processing，
Northwestern Polytechnical University，Xi′an 710072，China）
Abstract:The effect of solidified structure characteristics on heat-treated structures and rupture properties was studied in CMSX-2 single crystals with different arm spacing. The results show that，refining of solidified structures enhances the uniform degree of alloy structures，then improves the starting melting temperature of superalloy during solution treatment efficiently. In addition，structure refining can improve effect of heat treatment on rupture properties. The positive effect of superfining of solidified structures on mechanical properties of CMSX-2 superalloy is affirmed sufficiently by the experiment result in which the rupture lives of superfine dendrite single crystals are about 1.45 and 1.85 times those of the coarse dendrite single crystals respectively，in as-cast and heat-treatment condition.
Key words: single crystal superalloy; directional solidification; rupture properties; heat-treated structure; structure refining
