Accelerated abrasive wear of plastic parts in a piece of production machinery prompted a laboratory study to find a material with better abrasion resistance. The abrasion occurred in a machine that compacted 'sand-like' particles of an inorganic compound. The abrasion resistance of a wide variety of plastics and different durometer polyurethanes (21 materials) was tested with a modification of the ASTM dry-sand rubber wheel three-body abrasion test. Only one material, a polyurethane, had better abrasion resistance than the material that was currently in use. Hardness, friction and scratch tests were conducted on the test materials to try to understand the role of material properties in this type of abrasion. None of these correlated with the wear data. Previous investigators of plastic abrasion related abrasion resistance to the fracture energy and friction. The wear data developed in this study did not correlate with the specific model proposed by Ratner. However, it was possible to obtain a reasonable correlation with a deformation factor that included the friction of the abrasive on the plastic and a term that related to the energy required to deform the material plastically. A test similar to a Brinell hardness test was used to arrive at the deformation energy of the 21 test materials. The more easily the material deforms in contact with a particular abrasive, the better the abrasion resistance. (C) 1997 Elsevier Science S.A.
