The properties, performance, and reliability of a cermet material depend mostly on the intrinsic properties influenced by microstructure that evolves during processing and use. In this study, the effect of microstructure on reliability of multiphase materials in erosive media is analyzed with reference to WC-, TiC-, and Cr3C2 - based ceramic-metal composites. Microstructure of multiphase materials, fracture mechanisms, ability of energy dissipation, thermo-mechanical parameters and erosion resistance are examined. It has been shown that microstructural variables play a very important role in cermets performance. The energetic criterion of non-homogeneous materials selection has been presented.