High strength and plasticity TiBw/TA15 composites with a novel columnar network structure

In this paper, a novel columnar network structure reinforced TiBw/TA15 composites with excellent strength and high plasticity have been designed and prepared. To study the strengthening mechanism, the effects of the columnar network structure on the microstructure evolution and mechanical properties of the composites were investigated. The columnar network structure could effectively strengthen the grain boundary of the high temperature β phase and then enhanced the strength of the composites. At the same time, during the hot extrusion process, TiBw hindered the movement of dislocations and brought high distortion energy, which provided a favorable condition for dynamic recrystallization (DRX) of the matrix. DRX decreased the dislocation density, refined the grains, and then improved the plasticity of the matrix. Therefore, the effective combination of strength and plasticity was achieved in the composites.