Cutting performance and wear mechanism of Sialon ceramic cutting inserts with TiCN coating

• The TiCN coating is deposited on Sialon ceramic cutting inserts by PVD technique.
• The modulus, hardness, and adhesion force of the coating are 408.34 ± 16.25 GPa, 22.56 ± 0.99 GPa, and 33 N, respectively.
• Cutting performance of the inserts is improved remarkably by producing TiCN coating on the surface.
• The wear mechanism TiCN coated Sialon ceramic cutting inserts are abrasive and adhesive wear.

In this study, TiCN coating was deposited on Sialon ceramic cutting inserts by physical vapor deposition (PVD) technique. The properties of the coating were characterized by nano-indentation and scratch tests. The results showed that the elastic modulus, hardness, and adhesion force of the coating were 408.34 ± 16.25 GPa, 22.56 ± 0.99 GPa, and 33 N, respectively. Compared the Sialon ceramic cutting inserts with and without the coating, the surface hardness of inserts with the coating was higher than that of them without the coating, resulting in the outstanding cutting properties of the inserts. Cutting performance of the TiCN coated Sialon ceramic cutting inserts were investigated in turning nickel-based alloy under dry conditions. As a comparison, the uncoated Sialon ceramic cutting inserts for turning tests were performed under the same conditions. The results revealed that cutting performance of the inserts was improved remarkably by producing TiCN coating on the surface. The wear mechanisms of uncoated and TiCN coated Sialon ceramic cutting inserts were all abrasive and adhesive wear. However, the using life of TiCN coated inserts was much longer than that of the uncoated inserts, indicating that the coating can effectively protect the inserts from frictional wear.