WEAR CHARACTERISTICS OF A HARDFACED STEEL IN SLURRY

This study discusses some observations made during the wear testing of hardfaced layers deposited on a low carbon steel. Two kinds of (wear resistant) hardfacing materials were (separately) overlayed on a steel substrate and characterized for their microstructural features and we ar behaviour. Conditions of wear testing were varied in terms of the c ontent of sand particles in the slurry, the speed of rotation of the s pecimens and the distance traversed. The substrate material was also s ubjected to identical tests in order to assess the effects of hardfaci ng/overlaying. Hardfacing of the steel substrate resulted in a signifi cant improvement in the wear resistance (inverse of wear rate) over th at of the substrate, irrespective of the test conditions. Speed of rot ation had a mixed influence on the wear rate wherein the intermediate speed caused maximum wear loss. The distance traversed had a mixed inf luence on the wear rate of the specimens in the sense that in some cas es wear rate decreased with distance while a reverse trend was noted i n the remaining situations, whereas under one test condition, the wear rate first decreased with distance, attained a minimum and then again tended to increase. Moreover, the larger sand content in the slurry l ed to lower wear rates. The wear behaviour of the specimens has been e xplained on the basis of the predominating material removal mechanisms , such as erosion and abrasion, in different situations. These have be en further substantiated through their wear surface and sub-surface ch aracteristics. (C) 1997 Elsevier Science S.A.