RESISTANCE OF CAST POLYURETHANE ELASTOMERS TO SOLID PARTICLE EROSION

The rates of erosive wear have been measured for a series of eight polyester-based one-component castable polyurethane elastomers, with widely varying mechanical properties. Erosion tests were conducted with air-borne silica sand, 120 μm in particle size, at an impact velocity of 50 m s-1 and impact angles of 30° and 90°. For these materials, which all showed similar values of rebound resilience, the erosion rate increased with increasing hardness, tensile modulus and tensile strength. These findings are at variance with those expected for wear by abrasion, perhaps because of differences in the strain rate or strain levels imposed on the elastomer during erosion and abrasion. The appearance of the eroded surfaces in all these materials was similar to that seen in other elastomeric materials exposed to erosive wear, suggesting that the mechanisms of material removal were also similar. © 1990.