A Study of CrNiN, CrWN and DLC Films Deposited on AISI P21 Mold Steel

Autor: Ming-Cheng Yen, 顏名正
Rok vydání: 2012
Druh dokumentu: 學位論文 ; thesis
Popis: 100
AISI P21 is a commonly used material for the mirror surface of plastic molds. In this study, three different types of films, CrNiN, CrWN, and DLC films, were deposited on the AISI P21 by using Cathode Arc Plasma Deposition (CAPD) process. These specimens were analyzed by following methods: the surface morphology and roughness of the films were tested by AFM, the thickness and composition of the films were measured and analyzed by GDS, SEM, and EDS, the structure of the films were analyzed by XRD, the hardness and Young’s modulus of the films were analyzed by using Nano-indenter, the wear resistance and the coefficient of friction of the films were analyzed by using wear-test machine, the adhesion properties of the films were analyzed by using Rockwell C scale hardness tester, the corrosion resistance of the films were analyzed with corrosive tester, and the hydrophilic properties of the films were analyzed by using water contact angle tester. According to the experimental results, the thicknesses of the three films are individually 1.3 μm, 1.2 μm and 1.3 μm. The main characteristic peak of CrNiN and CrWN films are both (111), and the diffraction angle (2θ) are 37.47°, 38.21°. The hardness of AISI P21 substrate is Hv 372.98 and the friction coefficient is 0.63. Besides, the hardness of CrNiN, CrWN, and DLC films are eguivalent HV 2480.6, HV 2434.7, and HV 5238.73 respectively, and the coefficients of friction are 0.45, 0.34, and 0.29. Through the rockwell indentation test, the quality of the adhesion of the three films are HF3, HF2 and HF5. And the wear rate analysis of the three films is DLC < CrWN < CrNiN, and the minimum wear rate of DLC is 0.62×10-6 mm3/N-m. The corrosive test shows that there is a lower corrosive current of the DLC film, 3.527 × 10-9 A, which means the best corrosion of the three films is DLC. Finally, by using water contact angle test analysis, the water contact angles of the three films, CrNiN, CrWN, and DLC, are individually 78.5°, 85.3°, and 70.2°. It indicates the maximum water contact angle of the three films is CrWN film and there is a better draft performance. Through the above analytic results,, it can obviously enhance the hardness; lower the coefficient of friction, and improve the surface wear resistance by using CAPD process deposited CrNiN, CrWN, and DLC films on the surface of AISI P21.
Databáze: Networked Digital Library of Theses & Dissertations
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