Fretting Corrosion Characteristics Of Titanium And Titanium Alloys In Three Mediums

Fretting corrosion is one of the primary damage to metallic implants. Fretting corrosion often occurs in orthopaedic implants, for example between contacting surfaces of implanted plates and screws, stem of joint and cement, stem of joint and caput articularis. Most of studies in the literature are focused on various factors affecting fretting corrosion of metallic implants, whereas few investigations have been done on fretting corrosion behavior of metallic implants based on the theories of fretting regime and synergy.The fretting corrosion tests on ball-on-flat contacts of TA2 /TA2 and Ti6Al4V/Si₃N₄ have been carried out under the different media, normal load and displacement amplitude level using hydraulic fretting test machine with a high precision. Extensive analyses on Fretting Corrosion Characteristics of metallic implants have been performed based on fretting regime and synergy theories in combination with laser confocal scanning microscopy (LCSM), scanning electron microscopy (SEM), profilometer and optical microscope. The purpose of study is to provide experimental results and practical guide for the choise determination and exploitation of metallic implants and their clinical applications. A present study obtains the following conclusions:The fretting regime, friction coefficient and wear volume of TA2 and Ti6A14V depends strongly on displacement amplitude, normal load and experimental media. With the increase of displacement amplitude, it is found that the fretting regime changes from partial slip regime to mixed regime or slip regime; the coefficient of friction increases and wear volume rises. The transition of slip regime to mixed regime or partial slip regime, the decline of friction coefficient and the rise of wear volume can seen with the increase of normal load.In comparison with that in air, the fretting in distilled water and Saline solution is easily situated at mixed regime or slip regime,and fretting wear volume in Sline solution is smallest. The wear volume loss of Ti6A14V is largest in air and smallest in Saline solution, but that of TA2 is smallest in air.Fretting wear mechanisms of TA2 exhibits mainly the combination of...