Effect of substrate bias on structure and properties of (AlTiCrZrNb)N high-entropy alloy nitride coatings through arc ion plating

Abstract

This study mainly focused on the effects of different substrate bias on the microstructure, elemental composition, mechanical and tribological properties of (AlTiCrZrNb)N coatings. (AlTiCrZrNb)N high-entropy nitride coatings with different substrate bias parameters were deposited on cemented carbide and silicon wafers using arc ion plating. The results showed that the bias voltage created a high-energy particle bombardment effect to reduce the number and volume of macroparticles brought by arc ion deposition technology; this optimized the surface quality of the coating. (AlTiCrZrNb)N coatings at different bias voltages exhibited a single-sided cubic solid solution structure. Substrate bias can significantly change the preferred orientation of coatings. As bias voltage increased from 0 V to −100 V, the preferred orientation of coatings changed from (111) to (200), and when negative voltage further increased to 200 V, the preferred orientation changed from (200) to (111). Appropriate substrate bias parameters can improve the residual stress, mechanical properties, and tribological properties of coatings. The highest hardness of the coating reached 34.85 ± 2.05 GPa. The lowest average friction coefficient was 0.26, and the lowest wear rate was 8.86 ± 1.05 × 10−6 mm3 ∙ N−1 ∙ m−1.