Study on the microstructure and impact toughness of TC11 titanium alloy by a novel electromagnetic shocking treatment

Abstract

A novel electromagnetic shocking treatment (EST) has been put forward to optimize interface microstructure and further enhance the mechanical properties of titanium alloys. In details, tensile properties and impact toughness of TC11 titanium alloy have been investigated with room temperature tensile test and Charpy impact testing. Then, tensile fracture and impact fracture as well as microstructure including phase and interface are characterized and analyzed. The results show that after EST, the tensile strength increase slightly, the elongation decreases while the impact energy is enhanced obviously. Besides, with the maximum temperature rising on alloy sample surface being limited to just 210 °C, EST promotes the phase transformation from β to α instantly, also, wrinkling at interface is more commonly observed in EST sample, which indicates that nonlinear interface wetting and bridging are promoted by EST. It demonstrates that the increase of α mainly accounts for the slight improvement of tensile strength and the decrease of elongation. Also, considering that the phase transformation from β to α is unfavorable to the improvement of impact toughness, the degree of interface wetting and bridging which is dependent on the electromagnetic shocking energy plays a decisive role for the enhancement of impact energy of EST sample. This work provides a novel EST method to selectively embellish interface and further to improve the properties and performance of solid alloys related with interface microstructure.