Short-process thixoforming of nano-particles reinforced aluminium matrix composites with a high solid fraction

Abstract

ABSTRACT The composite components with complex-shape and containing different nanoparticle contents and sizes were successfully produced by the short-process thixoforming. Based on the developed constitutive model, numerical simulation of thixoforming for the composites with a high solid fraction was carried out, and the relevant experiments were performed. The influences of temperature and forming rate on strain-stress were analysed. Furthermore, the effects of temperature, moving rate of the die and holding time on the filling behaviour were discussed. Results of numerical simulation revealed that at high temperature and high forming rate, uniformly distributed stress-strain field and reduced maximum forming force could be obtained, which is advantageous for avoiding the non-uniform composition and incomplete filling caused by liquid-phase segregation; they were consistent with experimental results. After T6 heat treatment, the average yield strength and ultimate tensile strength of the parts were significantly improved. Moreover, the fracture mechanism of the part was discussed.