Load bearing implants such as hip joints, knee joints and bone plates etc. are prone to failure from the conjoint effect of wear, fretting and corrosion from the movement of body. Modular junctions of hip implants consist of ball on a shaft which is under sliding conditions during body movements like walking etc. Fretting is experienced at ball and shaft contact. Fretting wear or fretting fatigue is a form of adhesive wear phenomenon wherein a small tangential oscillatory motion under certain contact pressure gradually erodes the surface and initiates crack within the contact leading to ultimate failure of the material under fatigue loading condition. Titanium alloys, Stainless steels and Co-Cr-Mo alloys are most commonly used for medical grade devices. Titanium alloys has high strength to weight ratio, superior biocompatibility and corrosion resistance compare to other materials. Fretting fatigue life of surface modified titanium alloys has improved compared to unmodified materials due to enhancement in surface properties and reduction in friction.
Fler e-böcker från samma författare (r) / Redaktör
16 467 E-böcker i denna kategori
