Self-organization wear characteristics of MTCVD-TiCN-Al2O3 coated tool against 300M steel

The chemical thermodynamic of the cutting process was analyzed by Gibbs free energy function method. Tool life, wear characteristics, surface roughness and fractal characteristics of surface profile curves were investigated by high-speed turning of 300M with coated cutting tool. According to the chemical thermodynamic analysis, some products may be generated in this cutting system, which have a positive effect on high-speed cutting, such as TiO2 and SiO2. The reasons for the tool failure involved adhesive wear, abrasive wear, chipping, coating spalling and micro-crack. The self-organization wear characteristics (e.g. oxygen-containing surface layer and secondary structures) of the coated tool were found, which can play the role of protection, lubrication and heat insulation. The formation and disappearance of the self-organization structures affected the size of surface roughness. On the basis of the fractal analysis, a more stable and better machined surface quality was obtained at vc = 300 m/min which can be selected for finish machining.