Corrosion behaviour of porous titanium-graphite composites designed for surgical implants

Porous titanium is a popular surgical implant material. Its low elastic mod ulus encourages regular bone growth, whilst its porosity enables bone in-gr owth. Unfortunately, porous titanium has poor friction and wear properties. The addition of graphite, to lower the friction coefficient and titanium c arbide to increase wear resistance, could produce a multi-component materia l that overcomes these disadvantages. However, polarisation measurements re vealed that the graphite causes an increase in the titanium's corrosion rat e. Therefore, the extent that graphite can be used in porous titanium bioma terials will be a compromise between the benefits of improved friction prop erties against the disadvantage of increased corrosion. (C) 2000 Published by Elsevier Science Ltd. All rights reserved.