Establishment of Constitutive Relationships for Laminated Composites Considering the Variation of the Microhardness with the Strain in the Heterostructure Layers and Bonding Regions

A novel method is proposed to determine the constitutive relationship for a laminated composite by considering the strain-dependent microhardness of the heterostructure layers and bonding regions. A theoretical model is deduced to provide an analytical basis for the proposed method. The elemental and microhardness distributions of the heterogeneous layers and bonding regions of the TA1/Al1060/SS430 laminated composite were studied. Laws describing the variation of the microhardness of the heterogeneous layers and bonding regions with strain were obtained. A constitutive relationship for the heterostructure layers and bonding regions of the laminated composite was obtained. V-shaped bending finite-element analysis of a laminated composite using the determined constitutive relationship was conducted to verify its reliability. The proposed novel method may become a promising approach to study the plastic deformation behavior of laminated composites.