Microstructural effects in abrasive wear. Quarterly progress report for the period 15 June 1978--15 September 1978

Abstract

Low-stress and gouging abrasive wear was studied with respect to microstructure in a series of alloy white irons and Co-base powder metallurgy (PM) alloys. Tests have shown that low-stress abrasion resistance increases in a general way with hardness, whereas gouging wear resistance correlates to a significantly lesser extent. For gouging wear in particular, increasing hardness, carbon and alloy content are inefficient means to increase wear resistance. Low-stress rubber wheel abrasive tests (RWAT) have been conducted with unused and used SiO/sub 2/ and Al/sub 2/O/sub 3/, and sample weight loss and abrasive size degradation have been monitored. Relatively small changes in abrasive size distribution are found to be associated with marked differences in sample weight loss. Microtopographic analysis of the wear scars generated with all four types of abrasive indicate that wear-resistant alloys exhibit smoother wear scars. In gouging wear or in low-stress wear against SiO/sub 2/, maximum wear resistance is found at intermediate carbide volume fractions (v/sub f/) and matrix alloy contents. For low-stress testing against Al/sub 2/O/sub 3/, wear resistance increases linearly with v/sub f/.