(1. 兰州理工大学 甘肃省有色金属新材料省部共建国家重点实验室，兰州 730050；
2. 兰州理工大学 有色金属合金省部共建教育部重点实验室，兰州 730050)
摘 要: 采用XRD、SEM和EPMA技术研究MoSi2棒材的高温碳化行为。结果显示：试样心部仍为MoSi2相，碳化产物为Mo5Si3C和Mo2C；碳化层组织疏松，有大量圆形孔洞存在，厚度约为500~800 μm，心部组织表现为MoSi2沿晶和穿晶脆性断裂特征；碳化产物位于三元Mo-Si-C平衡相图中Mo5Si3、Mo5Si3C和Mo2C三相区内，试样由内到外，Mo2C含量逐渐升高；碳化产物主要由Mo5Si3碳化形成，而并非MoSi2的直接碳化产物。
关键字: MoSi2；碳化行为；Mo5Si3C；加热元件
（1. State Key Laboratory of Gansu Advanced Non-ferrous Metal Materials,
Lanzhou University of Technology, Lanzhou 730050, China;
2. Key Laboratory of Non-ferrous Metal Alloys, Ministry of Education,
Lanzhou University of Technology, Lanzhou 730050, China）
Abstract:The carbonation behavior of MoSi2 at high temperature was investigated by XRD，SEM and EPMA. The results show that the internal part of the sample consists of MoSi2. The major carbonization productions are Mo5Si3C and Mo2C. The structure of carbonized layer is loose and there is a large number of circular holes with thickness of about 500−800 μm. The internal microstructure of the specimen shows brittle fracture characteristics of MoSi2. The carbonized products locate at the Mo5Si3, Mo5Si3C and Mo2C three-phase region of the ternary Mo-Si-C equilibrium phase diagram. The content of Mo2C gradually increases from inner to extra of the sample. The carbonized products form from carbonizing Mo5Si3, rather than a direct carbonization product of MoSi2.
Key words: MoSi2; carbonation behavior; Mo5Si3C; heating element
