Titanium is a titanium-based alloy titanium bars by adding other elements. Titanium has two allomorphs: The following 882 ℃ is hcp α titanium, 882 ℃ or more for the body-centered cubic β titanium. Alloying elements according to their impact on the phase transition temperature can be divided into three categories: ① stable α phase, phase transformation element is α stabilizing element, aluminum, carbon, oxygen and nitrogen. Which is the main alloying elements aluminum alloy, it improve temperature and high-temperature strength of the alloy, reduce, and increase the elastic modulus had a marked effect. ② stable β phase, the phase transition temperature of the lower element of β stabilizing element, can be divided into the same crystal type and eutectoid two. The application of the titanium wire former molybdenum products titanium, niobium and vanadium; the latter are chromium, manganese, copper, iron, and silicon. ③ small element of the phase transition temperature of the neutral element, zirconium and tin.