Breaking through the dynamic strength-ductility trade-off in TiB reinforced Ti composites by incorporation of graphene nanoplatelets

Insight into the dynamic mechanical behavior of titanium matrix composites (TiMCs) under the extreme condition is requisite to provide improved understanding for the development of new protective materials. Here we reported a strategy to overcome the strength-ductility incompatibility in TiB whiskers reinforced titanium (TiBw/Ti) composites through tailoring a novel three-dimensional (3D) reinforcement configuration via the incorporation of graphene nanoplatelets (GNPs). Effects of GNPs addition on the spatial distribution of TiBw, interface microstructure and mechanical properties were investigated. Results evidenced that TiBw-(GNPs)/Ti composites showed concurrently enhanced dynamic strength and plasticity as compared to the conventional TiBw/Ti. The improved dynamic strength of TiBw-(GNPs)/Ti were derived from the alignment of 3D reinforcements, texture strengthening and GNPs-TiC synergistic effects. Stop-ring technology was introduced as the post-deformation analysis method. It turned out that the incorporation of GNPs induced higher thermal conductivity and strain-hardening capability, which delayed the formation of adiabatic shear bands. Moreover, considerable energy dissipation was required due to GNPs impeded the cracks propagation, which led to the improved dynamic plasticity.