The mechanical properties of skutterudite CoAs₃ by molecular dynamics (MD) simulation

Abstract

Skutterudite CoAs₃ is a potentially important thermoelectric material. Morse potential is employed here to carry out molecular dynamics simulations of nanobulk CoAs₃ at the temperature of 0 K. The stress-strain relationships under uniaxial tensile and/or compressive strain are obtained. The elastic modulus, extreme strength and deformation mechanism are studied. The simulation results indicate that nanobulk CoAs₃ abruptly ruptures at much higher strain level under tension than conventional bulk CoAs₃. Both the extreme stresses under tension and compression are much higher than those of conventional bulk CoAs₃.

Keywords

Skutterudite / thermoelectric / molecular dynamics / Morse potential

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