Surface modification of cemented carbide cutting tools for improved adhesion of diamond coatings

摘要

Diamond coatings are mainly used in cutting processes due to their tribological characteristics. They show a high hardness, a low friction coefficient, high wear resistance and a good chemical inertness. In relation to polycrystalline diamond(PCD)-tipped cutting inserts especially the advantageous chemical stability of diamond coatings is superior as no binder phases between diamond grains are used. However, the deposition of adherent high quality diamond coatings has been found difficult.Thus, substrate pretreatment is utilized to improve film adhesion. This investigation is based on water peening of the substrate material before coating. The investigation revealed results for diamond film adhesion on pretreated substrates compared toconventional diamond coatings on cemented carbide tools applied with the CVD hot-filament process. In final cutting tests with increased film adhesion water-peened cutting tools an improved were behavior was detected.