摘要
研究了在1700℃、Ar气氛下2D C/SiC-Mo反应偶的界面化学反应,利用XRD、EDS和SEM分析了反应界面的组成和微结构,讨论了界面反应机理;分析了反应偶材料热膨胀失配对界面残余应力的影响。结果表明:界面反应产物主要为Mo2C、Mo5Si3和Mo5Si3C,扩散路径可概括为Mo/Mo2C/Mo5Si3/Mo5Si3C/SiC;界面化学反应主要由元素的扩散控制,计算得出了在1700℃的扩散反应速率常数为1.05μm2/s;反应偶两种材料热膨胀系数的失配导致较大残余应力的产生,从而使反应界面在冷却后脱开。
The interfacial chemical reaction of 2D C/SiC-Mo reaction couples was investigated at 1700 ℃ in Ar atmosphere.The composition and microstructure of the interface layer were characterized by XRD,EDS and SEM.The reaction mechanism was discussed.The effects of interfacial residual stress on the thermal mismatch of the reaction couple were also analyzed.The results show that the interfacial reaction products mainly consist of Mo2C,Mo5Si3 and Mo5Si3C,and the diffusion path can be summarized as Mo/Mo2C/Mo5Si3/Mo5Si3C/SiC;the interfacial chemical reaction is controlled by mutual diffusion of the elements,and the diffusion rate constant K0 is 1.05 μm2/s at 1700 ℃;the interface debonds after cooling,because the great residual stress occurs due to the CTE mismatch of the two materials in the reaction couples.
出处
《热加工工艺》
CSCD
北大核心
2011年第10期80-83,共4页
Hot Working Technology
基金
国家自然科学基金重大研究计划重点支持项目(90916030)
关键词
2D
C/SIC
MO
反应偶
界面反应
扩散路径
2D C/SiC composite
Mo
reaction couples
interfacial reaction
diffusion path
