Fracture mode of Ti(C, N)-based cermets investigated by experiment and simulation calculation.

The high hardness and good wear resistance of Ti(C, N)-based cermets confer excellent applicability as cutting tools. However, the lack of in-depth research on the fracture mechanism limits further improvements in toughness. A typical commercial Ti(C, N)-based cermet with a core–rim structure was prepared through low-pressure sintering. The interface characteristics between the complex core, rim, and binder phases were characterized using transmission electron microscopy (TEM), while the actual hardness and modules of these phases were measured through in-situ nanoindenter assessments. The crack propagation behaviour of the cermet was analyzed using a 70° angle observation method combined with electron backscatter diffraction in scanning electron microscopy (EBSD/SEM). This study identifies a commonly occurring but long-overlooked fracture mode, termed "trans-rim" fracture. The experimental results were verified through simulation calculations. This novel idea offers insights into enhancing the toughness of Ti(C, N)-based cermets. [ABSTRACT FROM AUTHOR]