Nickel-titanium shape memory alloy has shape memory effect (SME), super elasticity (SE) and other functional properties, the surface state includes clean black oxide, bright and micro-oxide, using the international advanced micro nano cold processing technology prepared, wire diameter from 0.05mm to 2.0mm, commonly used in orthodontic archwire, root canal file, blood vessel guide wire, blood vessel stent, sports earphone, temperature control spring, robot and so on. Now the company can design and prepare a series of two-element or multi-element alloy ingots according to the requirements, the multi-element alloy elements include Cu, Cr, V, Co, Fe, Nb, etc. The processing state of the wire is cold processing or straightening, the surface state includes clean black oxide, bright and micro-oxide, the diameter of the wire is from 0.05mm to 2.0mm.