ABSTRACT
This chapter presents the major forms of surface damage and wear along with a proposed coding scheme. The diagnosis of wear problems can be made easier by adopting an organized, hierarchical system of surface damage classification. In contrast to single-occurrence surface damage, wear is generally considered to be progressive, involving multiple interactions. The phrase “alteration of a solid surface” replaced the earlier phrase “damage to a solid surface” in the definition because some ASTM committee members argued that machining or grinding could wear a surface intentionally and beneficially, yet not be considered “damage” with its negative connotation. The chapter describes the distinguishing features of several categories of wear based primarily on their relative motion and characteristic appearance. Polishing wear can be a tri-bochemical process that is facilitated by abrasive particles in a lubricant that remove oxide films while at the same time chemically attacking the surfaces.
