Effect of N₂ Flow Rate on Growth and Tribological Property of TiAlSiN Coatings on Carbide Substrate

Herein,we addressed the surface modification of carbide with TiAlSiN coatings,synthesized by pulsed DC magnetron sputtering.The influence of N₂ flow-rate on the microstructures and tribological properties was investigated with X-ray diffraction,scanning electron microscope,and conventional mechanical probes.The results show that the N₂ flow-rate had a major impact.To be specific,as the N₂ flow-rate increased from 40 mL/min to 100 ml/min,the size of columnar grain and residual stress decreased,resulting in an increasing compactness,the hardness and interfacial adhesion changed in a decrease-increase mode,accompanied by a stable elastic modulus.Deposited at 100 mL/min,the hardness increased to a peak of 25.2 GPa,the friction coefficient increased to a maximum of 0.55,and the wear-rate decreased to a minimum of 2.12. The low(high) N₂ flow-rate accounted for the major abrasive(adhesive) wear-mechanism of the TiAlSiN coatings,because of the increased compactness and hardness.