ABRASIVE WEAR OF PISTON RING AND CYLINDER BORE MATERIALS

Abrasion accounts for approximately 50 percent of all industrial wear, and in the internal combustion (IC) engine is probably the major reason for component deterioration. The main method of controlling the effects of the abrasive is to attempt to exclude them from reaching critical components by filtration. However, the efficiency of a typical engine filter is limited to particles greater than 25 microns squared. Therefore, debris of either a size less than this, or poor engine maintenance, will result in abrasive particles entering the system. (Over the last 20 years major progress has been achieved in extending the life of the IC engine by improvements in component manufacture, materials, fuels and lubricants as revealed in this Focus feature). From this examination, it was found that the presence of silica accelerated the initial running-in process of cast iron sliding against itself. However the wear mechanisms were unchanged. With wear plates of hardness greater than 500 Hv shearing of the wear pin is the predominent wear mechanism and hence wear rates are high. Three body abrasive wear predominates with the softer steels and cast iron wear plates. Hence the wear rates are lower.