Ti-6Al-4V(TC4) is a typical alloy in titanium alloys which can cover over half of the titanium market. TC4 was firstly developed by Illinois research institute America in 20th century and was one of the titanium alloys products at the earliest time. The element occurs within a number of mineral deposits, principally rutile and ilmenite, which are widely distributed in the Earth's crust and lithosphere, and it is found in almost all living things, water bodies, rocks, and soils.
Nowadays most of the titanium and titanium alloys are obtained by Kroll method-used Ca to substituted Mg as the reducing agent. At the end of the Kroll process, a titanium ingot is obtained then after mechanical working and heat treatment which are conducted below the beta transus temperature in order to get TC4. The raw material can be post processed by heat treatment, machining, welding. The high strength, low weight ratio and outstanding corrosion resistance enable its application fields cover from aerospace to medical industries.
Like other metals, titanium has distinct crystal structure, one is alpha-Ti(HCP) which is stable in cold condition, the other is called beta-Ti(BCC) which performs well in high temperature conditions.