低應力氧化鎢薄膜機械性質、抗磨耗性與應用於切削工具之磨潤特性研究

Tungsten oxide (WO3), a type of transition metal oxides, is well recognized by its stable chemical property and transition phases for many applications namely photocatalysis, sensing, and anti-abrasion coating. The excellent mechanical and anti-wear properties of tungsten oxide thin film could also improve the tribology behavior for many machinery applications. The optimized tungsten oxide thin film was created by electrodeposition for this study. The following parameters were carefully controlled during the thin film manufacturing process. Firstly, the process parameters and characteristic analysis were carried out, and the coating was performed on indium tin oxide (ITO) conductive glass and SKD-11 tool steel. Physical properties such as different film thickness and crystal form were obtained by controlling deposition time and heat treatment conditions. Furthermore, the film was measured by scanning electron microscope (SEM), X-ray diffraction (XRD), nanoindentation machine, abrasion testing machine and other instruments. The surface roughness, crystallinity, hardness, Young's modulus and anti-wear properties of the film were further studied. The experimental results show that proper control of the process parameters can form an even and complete tungsten oxide film on the flat substrate surface. In the unannealed and heat treatment conditions below 400°C, the subsequent heat treatment was the main factor affecting the crystallinity. The film exhibited amorphous under this treatment, while a cubic crystal structure was formed upon heat treatment over 500°C. The surface roughness, hardness, Young's modulus and other properties of the film are largely affected by the crystallinity. The surface roughness is low on amorphous film, and the heat-treated film has a larger surface roughness due to the gradual growth of the crystal grains. However, the surface roughness decreases after heat treatment over 500 °C. The experimental results show that the hydrophobicity of the film is impacted by the surface roughness. Moreover, the nanoindentation results showed that the Young's modulus and hardness of the film increases when temperature of the heat treatment increases. The results of the abrasion test confirmed that the film has a certain degree of anti-wear ability, and the anti-wear property will be enhanced when the heat treatment at 500 °C or higher.