Nanoprobe analysis of core-rim structure of carbides in TiC-20 wt% Mo₂C-20 wt% Ni cermet

In order to get detailed information of the core-rim interface of carbides in TiC-20 wt% Mo₂C-20 wt% Ni cermet, chemical analysis in the vicinity of the interface was carried out by energy dispersive x-ray spectroscopy equipped with a high-resolution transmission electron microscope (HRTEM) with a field-emission-type gun. It was found that the chemical composition discretely changed across the core-rim interface at a nanoscale level, whereas HRTEM observation revealed that the interface is highly coherent. The discrete change in molybdenum content at the interface may suggest the existence of a miscibility gap between TiC and MoC systems at the sintering temperature.