Showing papers by "T. Bell published in 1995"
TL;DR: In this paper, the critical ratios of coating thickness to indentation depth at which the substrate has various degrees of effect (2% and 10%) on the indentation response of the layered systems were discussed.
155 citations
TL;DR: In this article, H2S has been used to introduce sulphur species into the discharge atmosphere and the sulphur promotes the nucleation of the 8 phase, and a compound layer of thickness 30-45 μm with a duplex structure can be produced by this procedure on plain carbon steel and low alloy steel substrates.
Abstract: When a sulphur bearing gas is added to the nitrogen– hydrogen atmosphere used in a plasma thermochemical treatment, a nitrocarburising process can be performed because of the contribution from the carbon in the steel. In the present work, H2S has been used to introduce sulphur species into the discharge atmosphere. The sulphur promotes the nucleation of the 8 phase. A compound layer of thickness 30–45 μm with a duplex structure can be produced by this procedure on plain carbon steel and low alloy steel substrates. The outer zone (10–12 μm) is pure e phase and the innermost zone consists essentially of γ’ phase. The influence of the gas composition, temperature, and duration of the treatment on the microhardness profiles and thickness of the compound layer has been investigated. Wear tests, using a plain carbon steel substrate, revealed significantly better wear behaviour of the sulphur bearing nitrocarburised specimens, compared with materials treated by conventional plasma nitriding.
8 citations
TL;DR: Pin-on-disk sliding wear studies have been conducted on untreated and ion-implanted UHMWPE against an oxidised Ti-6Al-4V alloy and the enhanced mechanical and physical properties of the surface treated materials are responsible for the improved wear performance.
Abstract: Pin-on-disk sliding wear studies have been conducted on untreated and ion-implanted UHMWPE against an oxidised Ti-6Al-4V alloy. Under water lubricated conditions no wear was measured. The enhanced mechanical and physical properties of the surface treated materials are responsible for the improved wear performance which may be of great importance to orthopaedic prostheses.
4 citations