Synthesis and Microstructure of Liquid Phase Sintered MoCoB Based Cermet
MoCoB based cermets are prepared by tube furnace sintering under Ar atmosphere at different temperatures.The phase transformation,composition and microstructure evolution are studied by X-ray diffraction(XRD),Scanning Electron Microscopy with Energy Dispersive Spectroscopy(SEM/EDS).It is found that a small amounts of MoCoB hard phase which act as the seed crystal is produced via solid phase transformation below 1000℃,and a large amount of hard phase is grown in-situ in the liquid phase.An extremely rapid densification occurrs at the temperature of 1240-1250℃.In the present investigation,Mo-xB-50Co(at%)model alloys with four levels of Mo contents corresponding to Mo/B atomic ratio ranging from 0.85 to 1.17 are prepared to study the effect of the Mo/B atomic ratio on the microstructure of MoCoB-based cermets.With the increase of Mo/B ratio,the constitution of binder phase changes from(Co)to Co+Co3Mo,with the increase in the ratio of Mo/B.The hard phase grains exhibit rod-shape,when the composition of cermet reaches Mo-27B-50Co(at%),and while the Mo-rich phase appears when the composition reaches Mo-23B-50Co(at%).
Xu Zhifeng Yin Haiqing
University of Science and Technology Beijing,Beijing 100083,China
国际会议
北京
英文
928-937
2018-09-16（万方平台首次上网日期，不代表论文的发表时间）