Dry rolling-sliding wear of bainitic and pearlitic steels

Abstract The rolling-sliding dry-wear behaviour of a series of bainitic steels and a pearlitic rail steel has been investigated over a wide range of contact stress and creepage conditions. A wear-testing machine designed and built at Leicester — LEROS — allows very high contact stresses to be combined with high creepages under well-controlled conditions. Despite better standard mechanical properties, the wear resistance of the lower carbon bainitic steels was inferior to that of the pearlitic steel. A bainitic steel of the same carbon content as the pearlitic steel wore a little less, but at considerable expense to the counter-material in the wear couple. The wear resistance of the bainitic steels depends on the volume fractions of hard phases, carbide and martensite-austenite phase, for rolling-sliding as well as other types of dry-wear loading. Pearlite performs exceptionally well under rolling-sliding conditions since the lamellar microstructure is modified so as to present a greater area fraction of hard carbide plates at the wear surface, a fraction in excess of the bulk volume fraction of carbide. Recommendations are made for the application of these steels in rolling-sliding and other dry-wear circumstances.