Evaluating the role of particle distribution and shape in two-body abrasion by statistical simulation

Previous work suggests that particle shape—specifically, its variation with particle size—is unlikely to be the dominant cause of the particle size effect (PSE) encountered in abrasion. In theory, the statistically similar nature of particle geometry implies that wear rate in two-body abrasion should be independent of particle size when all other conditions are unchanged and boundary effects are negligible. In practice, however, the severity of wear can be influenced substantially by the cumulative effect of relatively small variations of each governing factor. This paper deals with numerous issues related to the shape of abrasive particles and surfaces, with the view of understanding how shape contributes to wear and the manifestation of the PSE. It has been discovered, for example, that among the various solids of revolution used in the past to model the asperities of particles, the most representative possesses a power-law generatrix. Particle shape alone, however, constitutes a modest part in determining the properties of abrasive tools, such as grinding wheels and abrasive coated paper. Consequently, the density and distribution of the particles on the surface must also be given due consideration. To this end a statistical simulation of two-body abrasion has been developed. The effects of varying asperity shape and distribution on wear rate are clearly demonstrated and compared to results obtained from two-body experiments.