钴基高温合金DZ40M高温高周疲劳过程中碳化物的行为  

Carbide Behavior during High Temperature High Cycle Fatigue in DZ40M Cobalt base Superalloy

作　　者：姜文辉[1] 姚向东[1] 管恒荣[1] 胡壮麒[1] 

机构地区：[1]中国科学院金属研究所

出　　处：《稀有金属》2000年第1期1-5,共5页Chinese Journal of Rare Metals

摘　　要：研究了ＤＺ４０Ｍ 合金９００ ℃高周疲劳过程中碳化物的行为。在９００℃疲劳试验过程中，ＤＺ４０Ｍ 合金中初生碳化物Ｍ７Ｃ３ 和ＭＣ发生溶解， 同时， 沉淀析出大量细小的二次碳化物Ｍ２３Ｃ６ ， 它与基体具有立方取向关系。Ｍ２３Ｃ６ 相钉扎位错及亚晶界， 强化合金基体， 提高形变抗力。初生碳化物发生了断裂， 降低了疲劳断裂抗力。ＤＺ４０Ｍ 合金表面发生了严重的氧化，优先氧化的碳化物是疲劳裂纹源。Abstract: The carbide behavior during high cycle fatigue at 900℃ in DZ40M alloy was investigated. The results show that primary carbides M 7C 3 and MC are dissolved and secondary carbide M 23 C 6 is precipitated profusely, which is assumed to be a cube cube orientation relationship with the matrix. M 23 C 6 pinns up dislocations and subgrain boundaries, strengthening the alloy matrix and increasing deformation resistance. The crack of primary carbides lowers fatigue fracture resistance. As high temperature fatigue appears, severe oxidation occurred on the specimen surface and preferentially oxidized carbide is a crack initiation site.

关 键 词：钴基 高温合金 定向凝固 碳化物 疲劳 氧化 

分 类 号：TG146.16[一般工业技术—材料科学与工程] TG132.32[金属学及工艺—金属材料]