微弧氧化製程對鈦基材之影響

Effect of the Surface Properties on Titanium Substrate by Micro Arc Oxidation

何奕融(Yi-Jung Ho)

指導教授 ： 唐自標

國立臺北科技大學/工程學院/材料科學與工程研究所/碩士(2013年)

https://doi.org/10.6841/NTUT.2013.00434

摘要

本研究藉由雙極脈衝電源供應器控制電源參數，使用矽酸鈉以及氫氧化鈉為電解液，以鈦為基材進行微弧氧化處理，探討改變陽極開壓時間、陽極關壓時間以及電流密度參數之影響。
結果顯示：藉由微弧氧化所生成之氧化層在XRD分析下，均有二氧化鈦之銳鈦礦（Anatase）相及金紅石（Rutile）相的繞射峰。在SEM觀察下，以Ton+為變數時，當其時間增加，表面生成物變得鬆散不密集，此因Ton+過長，造成局部性膜層的溶解大於膜層的成長。而Toff+為變數時，隨其時間增加，表面形貌明顯變得崎嶇，且生成物較密集。以電流密度為變數時，隨著電流密度提高，其表面形貌開始有局部面積產生片狀結構之現象。這是因為微弧氧化過程中，陽極對試片作功的能量及溫度較高，電弧能量越強，使試片發生大面積的熔融與凝固，所以產生大量局部之片狀結構。藉由橫截面做膜厚量測，以Ton+為變數，其在100us時有最厚之膜層約8.3um，當以Toff+為變數，其在500us時膜厚可達10.7um。而以電流密度為變數時，28.5（A/dm^2）下有最厚的膜層，約18.6um。由耐磨耗試驗分析發現，膜層表面明顯受到鉻鋼珠汙染。這表示磨耗試驗時，磨損是在鉻鋼珠上，而不是在微弧氧化後之二氧化鈦膜層上，故本實驗之膜層有提高耐磨性之效果。

關鍵字

微弧氧化 ； 金紅石 ； 磨耗測試

並列摘要

Pulsed bipolar power was used for MAO coating on titanium substrate. An aqueous solution containing Na2SiO3 and NaOH was used as electrolyte. Titanium as a substrate for MAO treatment, investigate Ton+, Toff+ and current density to titanium substrate of effect.
The XRD pattern obtained from the surface of the MAO coated specimen shows that the coating is formed from anatase and rutile. The formation of the strongest peak was due to the substrate. As we can see in the SEM image, the surface became porous when Ton+ much longer. Because long Ton+ were result in partial dissolution of the oxide film is greater than the growth of the oxide film. When Toff+ as variable, the result as opposite to Ton+. When current density as variable, there are some sheet structures on the coatings surface. The surface roughness of the coating is high. This is not surprising because the sparking on the surface of the substrate can make sparking channels and craters which make the surface rough. When Ton+ 100, the file thickness is nearly 8.3um, Toff+ 500, the file thickness is nearly 10.7um, when current density is 28.5（A/dm^2）, the file thickness is nearly 18.6um. The micrographs of the worn surfaces of the coated specimens, surface layer of chromium steel balls obviously been contaminated. According to the wear test, it means that the wear on the ball occurs in the chromium, instead of the surface of the MAO coated, therefore, the present study the effect of the film has improved abrasion resistance.

並列關鍵字

Micro arc oxidation ； Rutile ； Wear test

參考文獻

[1] F. Jin, P. K. Chu, K. Wang, J. Zhao, A. Huang, and H. Tong, "Thermal stability of titania films prepared on titanium by micro-arc oxidation," Materials Science and Engineering: A, vol. 476, 2008, pp. 78-82.

[2] L. A. Dobrzański, D. Pakuła, and E. Hajduczek, "Structure and properties of the multi-component TiAlSiN coatings obtained in the PVD process in the nitride tool ceramics," Journal of Materials Processing Technology, vol. 157-158, 2004, pp. 331-340.

[3] S. Mathur and P. Kuhn, "CVD of titanium oxide coatings: Comparative evaluation of thermal and plasma assisted processes," Surface and Coatings Technology, vol. 201, 2006, pp. 807-814.

[4] C. Fei, Z. Hai, C. Chen, and X. Yangjian, "Study on the tribological performance of ceramic coatings on titanium alloy surfaces obtained through microarc oxidation," Progress in Organic Coatings, vol. 64, 2009, pp. 264-267.

[5] N. K. Kuromoto, R. A. Simão, and G. A. Soares, "Titanium oxide films produced on commercially pure titanium by anodic oxidation with different voltages," Materials Characterization, vol. 58, 2007, pp. 114-121.