Cutting Performance of TiAlSiN Coated Cemented Carbide Tool with Post-Deposition Heat Treatment

In this study, TiAlSiN coatings were synthesized by cathodic arc deposition with Ti and Al88Si12 dual cathodes. The as-deposited coatings were following with post-deposition heat treatment in air and nitrogen atmosphere, respectively, at the temperature of 400 degrees C for 3 hour. The annealing treatment of the TiAlSiN coating has an expected effect on the wear resistance and cutting performance. The TiAlSiN coating subjected to heat treatment in nitrogen atmosphere presented the best oxidation and wear resistance among the tested coatings. The friction coefficient of the TiAlSiN coatings subjected in nitrogen atmosphere at 400 degrees C was decreased due to the effect of the structure modification by increasing hardness. Using thermogravimetric analyzer (TGA), the result turned out the lowest weight change of TiAlSiN coating after annealing treatment in air if compared to that of all the coatings. The reason my be due to the oxide layer formed on the coating surface acted as a protective layer. Cutting test on the hardened steel with mist oil lubricants, the TiAlSiN-coated WC-Co tool with annealing treatment in nitrogen provides the best wear resistance at the cutting edge.