Comparison in tool life of CVD deposited TiAlN coated HSS tool and uncoated HSS cutting tool through turning operation

In this work Titanium Aluminium Nitride (TiAlN) thin film has been deposited over high speed steel (HSS) single point cutting tool (SPCT) using thermal chemical vapour deposition (CVD) and a comparison in the tool life of TiAlN coated cutting and uncoated cutting tool has been accomplished through turning operation over a mild steel circular rod. The morphology and composition of TiAlN coated HSS cutting tool has been evaluated using scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) technique. The particle size of the thin film coating has been characterized using atomic force microscopy (AFM) technique. SEM images revealed columnar structure of TiAlN coating over the surface of cutting tool. EDS results revealed successful incorporation of Ti, Al and N element in HSS metal matrix. The surface roughness of the coating through AFM was observed as 12.6 nm. Through turning operation on a mild steel circular rod using lathe it was found that there is a considerable enhancement in the tool life of TiAlN coated HSS cutting tool as compared to the tool life of uncoated cutting tool.