Compositional effect on mechanical properties of transition-metal carbide solid solutions

Equiatomic multicomponent transition metal carbides containing different metal element numbers and carbide components were prepared from monocarbides by spark plasma sintering. The compositional effect on their mechanical properties were investigated in detail. Results indicate that all solid solutions exhibit higher hardness, strength, and modulus values than those obtained from rule of mixture, and it is prone to obtain higher mechanical properties in high-entropy compositions. Nevertheless, the variations of hardness, strength, toughness, and modulus show diverse trends upon the change of composition in carbide solid solutions. By comparison and analysis, it was concluded that entropy-related solid solution effect is a crucial parameter influencing the mechanical properties of metal carbides, however, other parameters such as microstructure, type of base monocarbides, phase purity are also negligible parameters which can have big influence on the overall mechanical properties.