A stator wedge (30) to position in a coil slot (40) for retaining coils (40) of a stator of a power generator and methods of forming the wedge (30) are provided. The stator wedge (30) preferably includes an elongate, non-conductive, and substantially rigid body member (36). The body member (36) preferably includes a relatively flat bottom surface (35) and a relatively flat top surface (33). The top surface (33) preferably has less surface area than the bottom surface (35). The body member (36) also includes at least a pair of side peripheries sloping upwardly from peripheries of the bottom surface (35) having a greater surface area to peripheries of the top surface (33) having a lesser surface area to thereby define at least a pair of angled sides (31, 37). A thin-film, abrasion-resistant, non-conductive coating layer (32) is formed on upper surfaces of at least the pair of angled sides (31, 37).