The density of titanium alloys is generally around 4.51g/cm3, only 60% of that of steel, and some high-strength titanium alloys exceed the strength of many alloyed structural steels. Therefore, the specific strength (strength/density) of titanium alloy is much higher than that of other metal structural materials, which can produce parts with high unit strength, good rigidity and light weight. Titanium alloys are used in aircraft engine components, frames, skins, fasteners and landing gear.