Constitutive model of elastic response for Fe-TiB2 composites

Abstract

The constitutive model of Fe-based matrix composites to the macroscopic stress was established for revealing the elastic response at multiscale. The effective elastic constants (EECs) of the Fe-TiB 2 composites were predicted by the constitutive model in this study, including the effective elastic modulus E ̅ , effective bulk modulus K ̅ , effective shear modulus G ̅ , and effective Poisson's ratio ν ̅ . And then, the diffraction elastic constants (DECs) related to the crystal planes ( hkl ), ν hkl and E hkl of the constituents of the composites, were also evaluated based on the multiscale correlation constitutive equations. Compared with experimental values, there was excellent agreement for the EECs of the Fe-TiB 2 composites and reasonable errors in DECs of the Fe-based matrixes and TiB 2 reinforcements. Furthermore, the multiscale coupling between the EECs and DECs related to elastic response and residual stress was also concerned in this micromechanical model. The internal stress in the TiB 2 reinforcements is higher than the Fe-based matrixes at the same applied stress of the composites, which means the desired load transfer has occurred.