Microstructure and Tensile Properties of Boron-Doped Beta Titanium Alloy

Abstract

The microstructural evolution and the mechanical properties of Ti-2Al-9.2Mo-2Fe-0.1B alloy during solution treatment and aging have been investigated. The experimental results showed that the addition of boron resulted in the formation of TiB phase and high level of recrystallization during hot deformation. TiB phase did not moved with the grain boundary migration during solution treatment. On aging, a little of α phase nucleated from the interface of TiB and β phase. The existence of TiB phase could offer the source of cracks during tensile deformation, resulting in the ductility decline of the alloy. In addition, the alloy which aged at 550°C and 600°C for 2h could obtain a good combination of strength and ductility, with 1100~1300MPa of ultimate strength and exceeding 7% of elongation.