Preparation and annealing study of TaNx coatings on WC-Co substrates

作者：Chen Yung I^*; Lin Bo Lu; Kuo Yu Chu; Huang Jen Ching; Chang Li Chun; Lin Yu Ting

来源：Applied Surface Science, 2011, 257(15): 6741-6749.

DOI：10.1016/j.apsusc.2011.02.115

• TaN
• Diffusion barrier
• Oxidation
• Cemented carbide
• Glass molding

To prevent Co diffusion from cemented carbides at high temperatures, we fabricated TaNx coatings by reactive direct current (d.c.) magnetron sputtering onto 6 wt.% cobalt cemented carbide substrates, to form diffusion barrier layers. Varying the nitrogen flow ratio, N-2/(Ar + N-2), from 0.05 to 0.4 during the sputtering process had a significant effect on coating structure and content. Deposition rate reduced as the nitrogen flow ratio increased. The effects of nitrogen flow ratio on the crystalline characteristics of the TaNx coatings were examined by X-ray diffraction. The TaNx coatings annealing conditions were 500, 600, 700, and 800 degrees C for 4 h in air. We evaluated the performance of the diffusion barrier using both Auger electron spectroscopy depth-profiles and X-ray diffraction techniques. We also investigated oxidation resistance of the TaNx coatings annealed in air, and under a 50 ppm O-2-N-2 atmosphere, to evaluate the fabricated layers effectiveness as a protective coating for glass molding dies.

• 出版日期2011-5-15