Research on Uniform Gas Distribution in Cathode System of PVD Coating Equipment for Cutting Tools

Abstract

To resolve coating appearance non-uniformity in industrial PVD-coated cutting tools, this study investigates cathode system gas distribution optimization. By analyzing the gas flow characteristics of single-nozzle-type gas pipelines, finite element simulations were employed to compare gas flow fields under equal hole spacing and gradient hole spacing configurations. Structural optimizations, including downward nozzle orientation and diffusion space enlargement, were proposed to eliminate jet flow effects. Experimental results demonstrated that the gradient hole spacing design significantly improved coating uniformity. Energy-dispersive spectroscopy (EDS) analysis revealed that the carbon content deviation among upper, middle, and lower samples was less than 10%, effectively resolving axial chromatic inconsistencies. This work establishes theoretical frameworks and technical protocols for PVD gas distribution uniformity, advancing product quality and batch consistency.