Effect of bias voltage on microstructure, mechanical and tribological properties of TiAlN coatings
(1. School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China;
2. Key Laboratory of Low Dimensional Materials and Application Technology of Ministry of Education, Xiangtan University, Xiangtan 411105, China;
3. Hunan Provincial Key Laboratory of High Efficiency and Precision Machining of Difficult-to-Cut Material, Hunan University of Science and Technology, Xiangtan 411201, China)
2. Key Laboratory of Low Dimensional Materials and Application Technology of Ministry of Education, Xiangtan University, Xiangtan 411105, China;
3. Hunan Provincial Key Laboratory of High Efficiency and Precision Machining of Difficult-to-Cut Material, Hunan University of Science and Technology, Xiangtan 411201, China)
Abstract: TiAlN multilayer coatings composed of TiAl and TiAlN layers were deposited on ZL109 alloys using filtered cathodic vacuum arc (FCVA) technology. The effect of bias voltage on the microstructure and properties of the coating was systematically studied. The results show that the coating exhibits a multi-phase structure dominated by TiAlN phase. As the bias voltage increases, the orientation of TiAlN changes from (200) plane to (111) plane due to the increase of atomic mobility and lattice distortion. The hardness, elastic modulus and adhesion of the coating show the same trend of change, that is, first increase and then decrease. When the bias voltage is 75 V, the coating exhibits the highest hardness (~30.3 GPa), elastic modulus (~229.1 GPa), adhesion (HF 2) and the lowest wear rate (~4.44×10-5 mm3/(N·m)). Compared with bare ZL109 alloy, the mechanical and tribological properties of TiAlN coated alloy surface can effectively be improved.
Key words: TiAlN coatings; filtered cathodic vacuum arc; bias voltage; microstructure; mechanical properties; wear