Titanium Alloy - Titanium Alloys Used Biomedically

Titanium Alloys Used Biomedically

• Ti-6Al-4V is cytotoxic due to its vanadium content. While having excellent biocompatibility, Ti-6Al-4V also suffers from poor shear strength and poor surface wear properties:

"Biocompatibility: Excellent, especially when direct contact with tissue or bone is required. Ti-6Al-4V's poor shear strength makes it undesirable for bone screws or plates. It also has poor surface wear properties and tends to seize when in sliding contact with itself and other metals. Surface treatments such as nitriding and oxidizing can improve the surface wear properties."

• Ti-6Al-7Nb was developed as a biomedical replacement for Ti-6Al-4V alloy because Ti-6Al-4V contains cytotoxic vanadium. Ti-6Al-7Nb contains 6% aluminium and 7% niobium.

"Ti6Al7Nb is a dedicated high strength titanium alloy with excellent biocompatibility for surgical implants. Used for replacement hip joints, it has been in clinical use since early 1986."