In this paper, we present the mechanisms of premature fracture modular neck stems in two case studies: (I) when and stem are both made same Ti6Al4V alloy, (II) from different alloys, CoCrMo alloy. Our study integrates orthopedic patients who have undergone primary uncemented THA for usual indications centers (Community Health Centre University Medical Centre). Both part national public health c...

Fretting damage to fuel rods reduces the service lives of the fuel assemblies and therefore increases reactor operating costs. The future development of fretting-resistant spacer grids necessitates the investigation of fretting behavior by means of model tests. This paper presents the results of such tests carried out to investigate fretting in three different fuel rod support configurations. T...

An investigation was carried out in order to study the fretting fatigue behavior of an AlSi9Cu2Mg aluminum alloy. The fretting fatigue tests of AlSi9Cu2Mg were performed using a specially designed testing machine. The failure mechanism of fretting fatigue was explored by studying the fracture surfaces, fretting scars, fretting debris, and micro-hardness of fretting fatigue specimens using scann...

Fretting wear and corrosion of Ti6Al4V alloys at the bone/implant stem interface produces the release of wear particles and corrosive ions from the stem into the surrounding tissue that can induce bone resorption. In this work, oxidation treatments at 500o and 700 oC for 1 h have been studied for increasing the friction-corrosion resistance at these interfaces. The friction-corrosion process of...

Corrosion of titanium dental implants has been associated with implant failure and is considered one of the triggering factors for peri-implantitis. This corrosion is concerning, because a large amount of metal ions and debris are generated in this process, the accumulation of which may lead to adverse tissue reactions in vivo. The goal of this study is to investigate the mechanisms for implant...

The mechanical and electrochemical behavior of the surface oxides of CoCrMo and Ti6Al4V alloys during fracture and repassivation play an important role in the corrosion of the taper interfaces of modular hip implants. This behavior was investigated in one group of CoCrMo and Ti6Al4V alloy samples passivated with nitric acid and another group coated with a novel TiN/AlN coating. The effects of m...

Fretting fatigue process have many features such as early stage crack initiation at contact edge, very slow crack propagation and fatigue failure after very long life operation. In this paper at first we present fretting fatigue model in high cycle region, which is considering the wear process near contact edge. And then we present fretting fatigue life estimation method in low cycle fatigue re...