Microstructures and properties of the Ti-3Al-5Mo-4.5V alloy

The microstructure evolution during the preparation process of BT16 titanium alloy wires, mechanical properties and cold upsetting performance of the wires, and microstructure of the solid-aged alloy were investigated by transmission electron microscope (TEM), scanning electronic microscope (SEN), optical microscope (OM) and X-ray diffraction (XRD). The results show that BT16 alloy wires have excellent mechanical properties with reduction of area Ψ 62%~65%. The cold upsetting bolt can achieve the head deformation of 75% without any defects. The titanium alloy ingot has dendritic α+β phases. Transverse section of the forged billet deforms unevenly and the equiaxial, the short-bar and the needle α phases precipitate. The hot forged bars have the fine needle α phase precipitation in the boundaries and grains. The microstructure of alloy wires consists of the primary equiaxial α phases and intergranular β phases. The microstructure of the solid-aged alloy is composed of equiaxial primary α phases and β phases which precipitate the secondary needle α phases.