Wear and microstructural studies of alloy sintered steels

Abstract

Crossed cylinder abrasive wear tests were carried out on alloy sintered steels T15, M2, and M42. The test parameters necessary for reproducible and reliable wear data have been studied. These parameters include applied load, time of test, abrasive grit size, speed of abrasion, and hardness of test specimen. Use has been made of the hypothesis of Archard to relate the test parameters to the wear rates found for these steels. Results show that Archard's hypothesis of abrasive wear holds for the conditions used in the test. The wear rates determined using this test method were found to be comparable to those observed in the use of these steels in industry and, therefore; it is considered that this method could be used to predict wear behaviour in service conditions. Using a replica technique on the polished and etched surfaces of these steels, it has been possible to make an assessment of the carbide size and distribution, both as number per cent and volume per cent. Examination of the microstructures of these steels showed a uniform distribution of carbide with a maximum size of 8 μm in a hardened and tempered steel matrix. The importance of microstructure in the characterisation of the wear behaviour of these alloy steels is discussed.

MST/1369