A GENERAL EQUATION OF COHERENCY STRAIN-ENERGY AND ITS APPLICATION

Abstract

Based on the macroscopic theory of elasticity, a general equation of coherency strain energy applicable to all crystal systems is derived by modifying Hilliard's method and the calculated results for some selected materials are graphically represented as the coherency strain energy map (CSEM). The complete equation is equivalent to those of Eshelby and Hay. In case of lacking of stress-free strain data, an assumption of hydrostatic stress for the internal stress is introduced to determine the relative variation of coherency strain energy with crystallographic orientation. The validity of the assumption is discussed in terms of the strain anisotropy.