Constitutive model of elastic response for Fe-TiB2 composites

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-TiB2 composites were predicted by the constitutive model in this study, including the effective elastic modulus E̅, effective bulk modulus K̅, effective shear modulus G̅, and effective Poisson's ratio ν̅. And then, the diffraction elastic constants (DECs) related to the crystal planes (hkl), νhkl and Ehkl 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-TiB2 composites and reasonable errors in DECs of the Fe-based matrixes and TiB2 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 TiB2 reinforcements is higher than the Fe-based matrixes at the same applied stress of the composites, which means the desired load transfer has occurred. [Display omitted]