A Comparison of Adhesive Wear with Three-Body Abrasive Wear Characteristics of Graphitic White Irons Designed for Metal-to-Metal Wear Systems

Frictional heat-induced severe adhesive wear has been limiting the lifetime of metal-to-metal wear systems for many years. Five graphitic white irons were previously designed and produced to introduce flake graphite into white iron, with the goal to expedite heat dissipation and reduce the frictional heat effect. This paper focused on the graphite addition effect on adhesive wear resistance for graphitic white irons and its comparison with abrasive wear. Adhesive wear resistance was assessed with a block on ring apparatus in accordance with ASTM G77. An empirical model was formulated to quantitatively evaluate graphite additions’ effect on the adhesive wear resistance. The model indicated that 1 vol.% graphite addition had the same effect as a hardness increase of 2.66 HRC, which was a 14% higher contribution than previously observed for three-body abrasive wear of the same alloys studied following ASTM G65. The improved wear resistance was related to an increased thermal diffusivity of the composite microstructure, and the surface lubricating effect of graphite.