Contact Corrosion Fatigue Of Bio-ceramicAlumina In Lactic Ringer’s Solution

Abstract

Ceramic materials have various superior characteristics in mechanical properties, heat resistance and chemical stability. To make the best use of these superior characteristics, ceramics have been considered as the candidate materials for biomaterials used for tooth root, artificial bone and so on. In recent years, the necessity of biomaterials has been increased more and more with an ageing society. Biomaterials mean the materials specially designed for the repair, reconstruction, and replacement of diseased or damaged parts of the human body. Apatite, glass ceramics, alumina and so on have been used as artificial bone and dental implant materials. From among these kinds of ceramic materials, alumina is a candidate material for bio-ceramics, because of its superior strength characteristics, corrosion resistance and bio-inert properties. To ensure the reliability of these bio-ceramics, various evaluations concerning degradation characteristics in aggressive environments such as the human body must be conducted. In previous papers, static fatigue and corrosion characteristics of alumina in isotonic sodium chloride solution were investigated. In this paper, the effects of body fluid corrosion upon contact fatigue behaviors of polycrystalline alumina have been investigated by conducting in vitro testing in lactic Ringer’s solution together with evaluating contact fatigue properties of Y-TZP. Also, degraded morphologies of the surface and fracture surface of the specimen were examined in detail by SEM and AFM. From these studies, the mechanism of contact corrosion fatigue of alumina was investigated by comparing with that of Y-TZP.