| Summary: | 碩士 === 明志科技大學 === 材料工程系碩士班 === 103 === Recently, the thin film metallic glass materials have attracted lots of attentions due to their unique mechanical and thermal properties. In this work, a series of W-contained and W-based thin film metallic glasses (TFMGs) were prepared by a magnetron co-sputtering system. In the first stage, the effects of tungsten content on the microstructure and mechanical properties of Zr-W-Si TFMGs were discussion. In the second stage, the Si element was used to replace Ti. The denser W-Zr-Si TFMGs were studied. In the third stage, the nitrogen was introduced in W-Zr-Si thin film metallic glass to form W-Zr-Si-N thin films. The amorphous structures of coatings were determined by a glancing angle X-ray diffractometer. The surface and cross sectional morphologies of thin films were examined by a scanning electron microscopy (SEM). The surface roughness of thin films was explored by an atomic force microscopy (AFM). A nanoindenter, a scratch tester and HRC-DB adhesion test were used to evaluate the hardness and adhesion properties of thin films, respectively. In addition, The anti-corrosion properties of TFMGs were evaluated by the potentiodynamic polarization tests in 5.0 wt.% NaCl aqueous solution. In this work, the Zr-W-Ti、W-Zr-Si and W-Zr-Si-N TFMGs all showed amorphous structure. An increase in tungsten content to effectively improve the hardness of the W-based TFMGs, reaching to the highest hardness of 13.3 GPa was discovered. Furthermore, the highest hardness can reach to 17.0 GPa with an appropriate amount of nitrogen addition. The Zr-W-Ti TFMGs exhibited a vein fracture pattern configuration, while the W-Zr-Si and W-Zr-Si-N TFMGs were columnar structures in the cross-sectional images. In this research, the corrosion tests showed that all TFMGs had excellent corrosion resistance than conventional SUS420 stainless steel. The Zr-W-Ti TFMGs provide an excellent adhesion and the adhesion quality was around HF1 to HF2 level. On the other hand, higher hardness and better corrosion resistance were achieved for the W-Zr-Si and W-Zr-Si-N TFMGs. Based on the above conclusions, the newly developed tungsten-based thin film metal glasses have considerable potential to be applied in industry.
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