Temperature-dependent elastic properties of binary and multicomponent high-entropy refractory carbides

Available information concerning the elastic moduli of refractory carbides at temperatures (T) relevance for practical applications is sparse and/or inconsistent. We carry out ab initio molecular dynamics (AIMD) simulations T = 300, 600, 900, and 1200 K to determine temperature-dependences constants rocksalt-structure (B1) TiC, ZrC, HfC, VC, TaC compounds as well multicomponent high-entropy (Ti,Zr,Hf,Ta,W)C (V,Nb,Ta,Mo,W)C. The second order are calculated by least-square fitting analytical expressions stress vs. strain relationships simulation results obtained from three tensile shear deformation modes. Moreover, we employ sound velocity measurements evaluate bulk, shear, Poisson's ratios single-phase B1 (V,Nb,Ta,Mo,W)C ambient conditions. Our experimental in excellent agreement with values AIMD simulations. In comparison predictions previous calculations - where extrapolation finite-temperature properties accounted thermal expansion while neglecting intrinsic vibrational effects produce a softening closer experiments. Results our show that system which exhibits highest resistances both up K, identify candidate require good ductility toughness room elevated temperatures.