Fatigue properties of cast and heat treated Ti-6Al-4V alloy for anatomic hip prostheses.
The intricate shape of Ti-6Al-4V anatomic hip prostheses necessitates the use of casting as a fabrication method, since neither machining, nor forging or powder metallurgial processing are reasonably acceptable. Cast and hot isostatically pressed Ti-6Al-4V, however, has a relatively low ductility and reduced fatigue properties. Appropriate thermal treatments can improve these properties. Specifically, treatments comprising a beta-solutionizing and an aging step yield ductilities similar to the forged and annealed condition, and fatigue properties 11.5% above the non-treated condition. Such treatments produce small alpha-beta platelet colonies with a ragged, tortuous morphology. The reduction of scatter in fatigue strength is the result of the formation of this well controlled microstructure.
D000497:Alloys; D004867:Equipment Design; D004868:Equipment Failure; D006622:Hip Prosthesis; D008669:Metallurgy / Q000379:methods; D013314:Stress, Mechanical; D013718:Tensile Strength; D014025:Titanium
D000497:Alloys; C031462:titanium alloy (TiAl6V4); D014025:Titanium