Yuntian T. Zhu¹, Xiaolei Wu²; ¹North Carolina State University, ²Institute of Mechanics

Heterostructured materials have been reported as a new class of materials with superior mechanical properties, which is attributed to the mechanical incompatibility. During their tensile testing, the soft domains will start plastic deformation with geometrically necessary dislocations piled up against the boundary with the hard domains. This produces back stress in the soft domains to make them appear stronger, while the stress concentration at the domain boundary exerts forward stress to the hard domain, making hard domain appear weaker. The combination of the back stress and forward stress represents hetero-deformation induced (HDI) stress to enhances the yield stress of the heterostructured material. The HDI stress also produces extra strain hardening to improve ductility. The “back stress” reported in the literature should be more accurately redefined ac the HDI stress. In this presentation, I’ll analyze the evolution of back stress and forward stress and raises issues for future study.