Mo_2FeB_2基金属陶瓷的相变及其显微组织演变研究Ⅱ:组织演变  

Investigation of Phase Transformation and Microstructure Evolution of Mo_2FeB_2-based Cermet II: Microstructure Evolution

作　　者：余海洲[1] 刘文俊[1] 张明松[1] 郑勇[2] 

机构地区：[1]三峡大学机械与材料学院,湖北宜昌443002 [2]南京航空航天大学材料科学与技术学院,江苏南京210016

出　　处：《硬质合金》2011年第4期199-205,共7页Cemented Carbides

基　　金：湖北省自然科学基金资助项目(No.2009CDB260);华中科技大学塑性成型模拟及模具技术国家重点实验室开放基金项目(No.09-14)

摘　　要：本文运用XRD和SEM等研究了不同烧结温度和保温时间下Mo2FeB2基金属陶瓷显微组织演变规律。结果表明:Mo2FeB2硬质相在固相烧结阶段生成,其颗粒形貌为等轴状。在液相烧结过程中随烧结温度的升高,粘结相团聚程度逐渐降低,组织逐渐均匀;同时硬质相颗粒柱状生长,粘结相中Mo元素固溶量增加。高温保温过程中,部分硬质相颗粒出现异常长大,异常长大的大颗粒总是伴随着颗粒合并。The microstructure evolution of Mo2FeB2-based cermet was studied at different sintering temperatures and dwell times by means of X-ray diffraction （XRD） and scanning electron microscopy （SEM）.The results show that the Mo2FeB2 grain,which is formed at the stage of solid phase sintering,exhibits equiaxed morphology.With the increase of sintering temperature,the aggregation of binder phase is decreased,the microstructure gradually becomes uniform;the columnar grain of hard phase grows,and the solid solubility of Mo element in binder phase is increased.A part of hard phase grain appears abnormal growth during the high temperature dwell stage,and the abnormal growth of the grain is always accompanied by the grain coalescence.

关 键 词：MO2FEB2基金属陶瓷 显微组织 柱状生长 异常长大 

分 类 号：TG148[一般工业技术—材料科学与工程]