INTRODUCTION Wear of ultra-high molecular weight polyethylene (UHMWPE) in total knee replacements remains a major limitation to the longevity of these clinically successful devices [1]. Improvements in sterilization techniques over the past decade have reduced oxidative degradation of the UHMWPE bearing, with potentially dramatic long-term reductions in fatigue-related pitting and delamination ...

Al7075 alloy reinforced with h-Boron Nitrate (BN) composites were processed by stir casting technique. The produced composite was subjected to microstructural studies using OLYMPUS -BX51M, tensile, hardness, density and wear tests. Tensile strength and hardness were found to increase by 12.8% and 20% respectively due to increased dislocation density with the addition of reinforcement. Microstru...

The predominant cause of late-state failure of total hip replacements is wear-mediated osteolysis caused by wear particles that originate from the ultrahigh molecular weight polyethylene (UHMWPE) acetabular cup surface. One strategy for reducing wear particle formation from UHMWPE is to modify the surface with a hydrophilic coating to increase lubrication from synovial fluid. This study focuses...

Abstract: Austenitic stainless steels exhibit a low hardness and weak tribological properties. The wear behaviour of austenitic stainless steel AISI 316 was evaluated through the pin on disc tribological method. For investigating the effect of wear on the changes in microstructure and resistance to wear, optical microscopy and scanning electron microscope were used. The hardness of the worn...

An investigation of the friction and sliding wear of gray cast iron against chromium plated cast irons was carried out on a newly constructed reciprocating friction and wear tester. The tests were the first to be done on the test rig under dry conditions and at the speed of 170 cm/min, and variable loads of 20-260 N for a duration of 15 min. to 3 hours. The gray cast iron surfaces worn by a pro...

The presence of oxygen in the environment in which a steel sliding system operates will promote a mild form of wear with wear debris consisting mainly of iron oxides. Of the oxidation-dominated mechanisms, mild-oxidational wear (the prefix describes the extent of oxidation and not the wear rate) has been most extensively investigated. In this paper, examples will be used to show that the wear-m...

B4C ceramic particulate–reinforced Al 5083 matrix composite with various B4C content was fabricated successfully via hot-press sintering under Argon atmosphere. B4C particles presented relative high wettability, bonding strength and symmetrical distribution in the Al 5083 matrix. The hardness value, friction coefficient and wear resistance of the composite were higher than those of the Al 5083 ...

Using high-resolution, in situ imaging of a hard, wedge-shaped model asperity sliding against a metal surface, we demonstrate a new mechanism for particle formation and delamination wear. Damage to the residual surface is caused by the occurrence of folds on the free surface of the prow-shaped region ahead of the wedge. This damage manifests itself as shallow crack-like features and surface tea...

Oxidative degradation of ultra-high molecular weight polyethylene (UHMWPE; PE), due to gamma irradiation sterilization in air, increases wear rate in artificial joint. Not only adhesive and abrasive wear but also delamination (flaking), a typical wear of the PE component in artificial knee joint, and fracture could be observed. This paper deals with gamma-irradiation effects on severe wear mech...

The diamond-like carbon (DLC) films deposited on the articulating surface of medical-grade Ti and Ti–6Al–4V were characterized. The DLC films were synthesized by r.f. plasma assisted chemical vapor deposition (PACVD) using C6H6 at 10 mTorr. For wear tests, the ball-ondisk type wear tester was employed by wearing a 5-mm diameter ruby ball against a rotating metal disk. The DLC coating dramatical...