高Cr镍基单晶合金1050℃的高温氧化性能.pdfVIP

学兔兔 Feb．2011 铸 造 VoI．60 NO．2 FOUNDRY ·175· 高Cr镍基单晶合金1 050 oC的高温氧化性能 卢旭东 一，田素贵 ，别、振东 (1．沈阳工业大学，辽宁沈阳110178；2．沈阳理工大学，辽宁沈阳110159) 摘要：采用x射线衍射 (XRD)、扫描电镜 (SEM)及能谱 (EDAX)等手段，研究了一种高cr镍基单晶高温合金在 1 050℃的高温氧化行为。结果表明，氧化初期合金增重迅速，氧化增重不遵循抛物线规律，表面氧化膜出现剥落，氧化 过程由形成Al2O，和cr O，所控制。高温氧化期间，合金发生明显的外氧化和内氧化，外氧化膜由Cr20，和 (Ni，Co)Cr20 组 成，内氧化物为AI 0，。在内氧化物上方出现贫Al富Ta区，元素贫化区尺寸随时间的延长而增大，富Ta相抑制基体中Al 向外扩散，并抑制氧化膜生长。 关键词：镍基单晶合金；高温氧化；内氧化 中图分类号：TG132．3+2 文献标识码：A 文章编号：1001—4977(2011)02—0175—05 Oxidation Behaviour of a High Chr0mium Single．CrystaI Ni．Base Superalloy at 1 050℃ LU Xu—dong 一，TIAN Su-gui ，SUN Zhen—dong (1．Shenyang University of Technology，Shenyang 1 1 01 78，Liaoning，China； 2．Shenyang Ligong University，Shenyang 1 1 01 59，Liaoning，China) Abstract：The high temperature oxidation behavior of the single．crystal Ni-base superailoy with high Cr content was investigated at 1 050℃ in air by using of SEM．XRD and EDAX．The results show that the mass gain rapidly increases in the initial stage．and the kinetic curve of the alloy does not obey the parabolic Iaw；a smalI amount of oxide scale spallation happens in the course of oxidation f0r 31 7 h and the oxidizing process iS mainly controlled by the formation of Cr203 and AI2O3 phases． An obvious oxidation and internal oxidation occurs during oxidation at 1 050℃．The oxides in the outer layer consist of Cr203 and(Ni，Co)Cr204，while the internal oxide iS AI2O3 only．The poor-aluminum but rich-tantalum areas appear above the internaI oxides．the size of the poor-aluminum areas increases gra