Effect of carbon content in TiC_xN_(1-x) coating on the adhesivity of carbide cutting tools and machining performance

摘要

Titanium carbonitride (TiCN) is a popular hard coating for carbide cutting tools in various applications. This paper studied the influence of the carbon content and coating composition within TiC_xN_(1-x) coatings with regard to their adhesive strength on tungsten carbide substrate and subsequently, the performance of cutting tool in the dry turning of stainless steel. Among all the TiC_xN_(1-x) coatings, the TiCN coating has exhibited the highest adhesivity onto a substrate, followed by a TiC coating and lastly, a TiN coating. It was found that the adhesive strength of TiCN coating increased with the carbon content. The C/N ratio or C-N bond is a vital contributor to the adhesivity of the TiC_xN_(1-x) coating rather than the C or N atoms in the TiC_xN_(1-x) coating. It was found that the coating was delaminated before the exposure of substrate material. Hence, coating with higher adhesivity will promote longer tool life.