What's the difference between titanium alloy and titanium nail?

Titanium nails are made of medical titanium.
Medical titanium is a metal used in the manufacture of medical devices, prostheses or auxiliary therapeutic devices implanted in the human body.
Medical titanium has excellent corrosion resistance, elastic modulus close to that of natural bone, and excellent biocompatibility. Medical pure titanium is single-phase structure, can not be strengthened by heat treatment.
It is divided into 1, 2, 3 and 4 levels according to the content of impurity elements such as carbon, iron and oxygen.
Medical titanium is used for internal bone plates, bone screws, dental implants, etc. Titanium mesh or titanium plate is also used to make artificial skull, artificial heart valve, cardiac pacemaker and titanium alloy for radiotherapy, etc.
Titanium is an important structural metal developed in the 1950s. Titanium alloy has high strength, good corrosion resistance and high heat resistance. In the 1950s to 1960s, mainly the development of high temperature titanium alloy for aeroengine and structural titanium alloy for the body, the 1970s developed a number of corrosion resistant titanium alloy, since the 1980s, corrosion resistant titanium alloy and high strength titanium alloy has been further developed. Titanium alloy is mainly used in aircraft engine compressor components, followed by rocket, missile and high-speed aircraft structural components