Microstructural effects in abrasive wear. Quarterly progress report, 15 September--15 December 1977

Abstract

A series of alloy white irons and Co-base superalloys are being tested for low-stress abrasion resistance in a rubber-wheel abrasion test (RWAT) and for gouging wear resistance in a grinding wheel test (GWAT). The objective of the tests is to establish general relations for the improvement of wear resistance by the control of microstructure. Wear testing results on the white irons indicate that microstructural factors such as carbide shape, volume fraction and the presence of retained austenite greatly influence wear resistance. Macrohardness provides a good measure of low-stress wear resistance, but is less effective as a measure of gouging wear resistance. In cases of uniform matrices, matrix microhardness, rather than carbide microhardness, correlates with both low-stress and gouging wear resistance. For Ni-Hard 4 white iron, RWAT and GAWT wear resistance can be correlated with mechanical properties obtained in compression, fatigue, impact and fracture toughness tests. The most direct correlations are obtained for hardness and compression tests.