Four-parameter equation of state and determination of the thermal and mechanical properties of metals

A four-parameter equation of state (EOS), expressed in terms of the equilibrium volume V0, cohesion energy EC, isothermal bulk modulus B0 and its first pressure derivative B′0B′0, is proposed and proved to performance better for 40 selected metals than the well-known Rose and Vinet equations. Based on the proposed EOS, the thermal expansions α, melting points TM, ultimate strengths PC and critical volume VC are calculated, and interestingly, a unique correlation is observed for all the studied metals, i.e. PC/B0(VC−V0)/V0≈0.31. It turns out that the calculated results are in good agreement with the experimental observations.