Architecture Dependent Strengthening Mechanisms in Graphene/Al Heterogeneous Lamellar Composites

An architecture-based model revealing the architecture-strengthening mechanism correlations of Graphene/aluminum (GR/Al) composites with heterogeneous lamellar (HL) architecture is proposed. The microstructural features such as matrix grain size, shape, and orientation in HL GR/Al composites are drivers for the dislocation storage and strain hardening ability. In this work, an architecture-based constitutive model is developed, which allows to describe the role of the HL design factors affecting the microstructural architecture in GR/Al composite and the strengthening mechanisms of the material. The improved mechanical properties are linked to strain hardening ability the high dislocation storage capability of the CGBs as well as the generation of further geometrically necessary dislocations (GNDs) in the GR/Al interfaces. Moreover, the optimal-alignment of the structural elements and GRs not only cause a combined effect of isotropic and kinematic strain hardening but also lead to higher levels of back stress and back stress hardening, respectively. Actually, the significant effect the interfacial dislocations including GNDs on the internal stresses especially back stress, which leads forming the extra strain hardening is underlined. In a word, the proposed model, which is based on the dislocation induced strengthening mechanisms, enable to guide the processing-microstructure design