Titanium is widely used in aerospace technology, high-performance materials, light weight, high strength, toughness, corrosion resistance is its most notable features. Titanium bolt is also the only high strength, low density, excellent resistance to fatigue and corrosion resistance, and low elastic modulus material, widely used in medical equipment, chemical equipment, military and sports equipment and other fields . Particularly suitable for aerospace, military, ships, automobiles, bicycles, motorcycles, oil, chemicals, machinery and electronics, hardware accessories and other industries. (Material properties: the material composition of TC4 titanium alloy Ti-6Al-4V, is (a + b) titanium alloy, has good mechanical mechanical properties, more than strength. TC4 intensity sb = 1,012 MPa, the density g = 4.4 × 103, than the strength of sb / g = 23.5, while the specific strength alloy steel sb / g less than 18.)