Development of cored wires for improving the abrasion wear resistance of austenitic stainless steel

Arc-sprayed coatings are an attractive means to protect components from abrasive wear provided they contain enough hard phases. Because of their hardness and toughness, 316L-TiB2 cermets were selected as the basis for developing wear-resistant coatings. Cored wires composed of type 304 stainless steel sheaths filled with 10 to 65 wt% TiB2,1 to 15 wt% additives, and the balance with 316L stainless steel were fabricated and arc-sprayed with air. The arc-sprayed stainless steel-TiB2 coatings were abrasion tested and the volume loss measured with an optical profiloineter. The volume loss decreased as the proportion of TiB2 increased. However, large differences in volume loss between coatings that contain about the same volumetric proportion of hard phases cannot be explained by a linear relationship. An inverse rule of mixing was proposed and found useful in determining the influence of different additives. Tin, added in the core as a fugitive liquid transfer agent, was the most powerful additive for improving the wear resistance of stainless steel-base coatings. These advanced arc-sprayed stainless steel-TiB2 coatings exhibit greater wear resistance than those obtained by arc spraying commercial solid and cored wires.