Influence of pulse length and N₂ flow rate on Cr_xN coatings prepared by HiPIMS

Cr_XN coatings were fabricated using High-Power Impulse Magnetron Sputtering (HiPIMS). The influence of pulse length and nitrogen (N₂) flow rate on the microstructure and performance of the coatings was systematically investigated. Long-pulse (100 μs) and short-pulse (50 μs) modes were employed under varying N₂ flow rates (5–35 sccm) to evaluate their impact on coating composition, crystalline phases, mechanical properties, and electrochemical corrosion resistance. Short-pulse mode effectively mitigates target poisoning, sustains high ion bombardment density, and significantly enhances coating density, hardness (40.8 GPa), and corrosion resistance. In contrast, the long-pulse mode achieves enhanced mechanical and corrosion resistance properties at low N₂ flow rates, primarily due to reduced target poisoning and higher peak currents. The findings provide theoretical and practical insights for optimizing HiPIMS parameters to achieve tailored coating performance in diverse application environments.