Papers by Keyword: Two-Body Abrasion

Abstract: The friction and wear properties of Polytetrafluoroethylene (PTFE) coatings before and after gamma irradiation were studied under vacuum conditions. Experimental results indicated that the friction and wear properties of PTFE coatings were improved by gamma irradiation. Results showed that the wear process of PTFE coatings before and after gamma irradiation consists of three stages. The steps for the irradiated PTFE are slightly longer than that for the non-irradiated samples. The friction coefficient of irradiated PTFE coatings reduces slightly compared to that of the non-irradiated samples. The friction coefficients of the PTFE coatings before and after gamma irradiation first increase with the increase of sliding velocity and then decrease with the increase of sliding velocity, and The friction coefficient of PTFE coatings before and after gamma irradiation decreases with the increase of load. The wear of irradiated PTFE coatings is slightly lower than that of non-irradiated PTFE coatings. The wear of PTFE coatings before and after gamma irradiation first decreases with the increase of sliding speed and then increases as the sliding speed increases. The wear of PTFE coatings first decreases with the increase of load and then increases with the increase of load. Scanning electron microscope (SEM) was utilized to investigate the worn surfaces.

Abstract: Metal-bonded diamond impregnated tools are being increasingly used in the processing of natural stone, sawing and drilling concrete and brickwork, road repair, petroleum exploration, production of ceramics, cutting frozen foods, etc. Although the main tool wear mechanisms seem to be well identified, the scientific background is still inadequate and extensive fundamental research has to be carried out to better understand how the tool performs in actual applications. This work attempts to address the complex issues of modelling the abrasive wear of the metallic matrix under laboratory conditions. In view of the generated wear data, it becomes evident that a comprehensive characterisation of the matrix’s susceptibility to wear by 2-body and 3-body abrasion can be reliably assessed in a quick and inexpensive manner; whereas tests carried out on diamond impregnated specimens may assist in the prediction of the tool life in abrasive applications.

Abstract: To understand the mechanism involved in the lapping process of the silicon nitride balls, the wear mode is investigated in this paper. The abrasion tests were performed on a ball-plate wear test apparatus with different loads (0~2N/ball) and slurry concentrations (5%wt~30%wt W20 B4C3). The abraded surface is observed by optical telescope. A wear-mode map, which defines the regimes for two-body abrasion or three-body abrasion dominating in the micro-scale abrasion test, is plotted with two axes: load and concentration of abrasive. An empirical formula for the wear mode transition is adopted to calculate the transition point S*, which can then used to predict the wear mode in lapping process of silicon nitride ball.