Effects of duty cycle on microstructure of TiN coatings prepared using CAE/HiPIMS

This paper reports on a novel HiPIMS-assisted CAE deposition process using a Ti target for the fabrication of TiN coatings on WC substrates. Our primary objective was to elucidate the influence of duty cycle on the microstructure and mechanical properties of the TiN coatings. Optical images revealed that decreasing the duty cycle led to a corresponding decrease in the number and size of surface macro-particles. A duty cycle of 3% was shown to maximize the flux of ion bombardment, which in turn maximized the number of nanocrystals, while minimizing the size of grains and columnar crystals. The resulting coating presented outstanding hardness (33.6 GPa), elastic modulus (507 GPa), and wear rate 3.32 (10−6 × mm3N−1m−1). •This study used HiPIMS to augment a CAE system for the deposition of TiN films.•The number and size of MP on the surface were proportional to duty cycles.•Decreasing duty cycle decreased the wear rate from 6.1 to 3.3 × 10−6mm3N−1m−1.•The grain refinement and nanocrystalline structure were found for duty cycle of 3%.