| TiN has been applied to wear resistant coatings in cutting tools and bearings by PECVD, Sputtering and Ion Plating. Most of the TiN depositing processes take advantage of plasma assistance in lowering required substrate temperature for commercial tool materials like toos steels and high speed steels. BARE(Biased Activated Reactive Evaporation) has wide applications in compound film deposition at low substrate temperature. The plasma density is the main factor to activate the compound formation reaction and to enhance the adhesion between TiN film and the substrate material. In this study, the direct comparison of coatings` performance by screech machining test was carried out for various discharge conditions including the substrate bias, the anode current, and the partial flow rate of less active gas, N₂. The machining life was more dependent on the adhesion than films` microhardness. The maximum increase of machining life was 15 times as the uncoated drills. On the average, 5 times increase was achived with gold color TiN coated high speed steel drills. |
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