Properties of TiAlN Coatings Obtained by Dual-HiPIMS with Short Pulses

Abstract

The paper focuses on the dual high-power impulse magnetron sputtering of TiAlN coatings using short pulses of high power delivered to the target. The surface morphology, elemental composition, phase composition, hardness, wear resistance, and adhesive strength of TiAlN coatings with different Al contents were investigated on WC–Co substrates. The heat resistance of the TiAlN coating was determined with synchrotron X-ray diffraction. The hardness of the TiAlN coating with a low Al content ranged from 17 to 30 GPa, and its wear rate varied between 1.8∙10−6 and 4.9∙10−6 mm3·N−1·m−1 depending on the substrate bias voltage. The HF1–HF2 adhesion strength of the TiAlN coatings was evaluated with the Daimler–Benz Rockwell C test. The hardness and wear rate of the Ti0.61Al0.39N coating were 26.5 GPa and 5.2∙10−6 mm3·N−1·m−1, respectively. The annealing process at 700 °C considerably worsened the mechanical properties of the Ti0.94Al0.06N coating, in contrast to the Ti0.61Al0.39N coating, which manifested a high oxidation resistance at annealing temperatures of 940–950 °C.