- 學位論文
電解液添加氯化鈣對純鈦微弧氧化膜層之影響
Effects of calcium chloride electrolyte on properties of micro-arc coatings on pure titanium
摘要
本實驗是利用微弧氧化在純鈦基材上，生成多孔性的氧化陶瓷膜層，大部分研究使用甘油磷酸鈉溶液當作含有磷酸根離子，以醋酸鈣當作含有鈣離子，搭配當作電解液，但是甘油磷酸鈉溶液價格昂貴，又必需添加助導劑與螯合劑。 本實驗利用價格相對較低，但同樣含有鈣離子的氯化鈣和含有磷酸根離子的甘油磷酸鈣取代，在固定電解液中的鈣磷比，以定電壓雙極脈衝的方式，探討在不同電壓與不同含量的氯化鈣添加，對微弧氧化陶瓷膜層的影響。 由實驗結果可以得知，當氯化鈣添加後會造成膜層厚度跟粗糙度上升，原因是因為氯化鈣的導電度較好，造成電流上升，使得反應劇烈，當氯化鈣添加到0.03M，而電壓升到310V，會造成膜層崩落，導致膜厚與粗糙度下降，再由SEM圖觀察可發現到，添加氯化鈣孔洞會變大，形狀由圓形逐漸轉變成橢圓或者不規則形，至於親水性測試，在添加氯化鈣之後，水接觸角都有明顯下降，從XRD的結果來看，在電壓達到280V後會生成鈣鈦礦結構與α-Ca3(PO)2，而無生成氫氧基磷灰石。
並列摘要
Most of coatings on pure titanium were fabricated in a solution containing glycerophosphate and calcium acetate. In this study, porous ceramic oxide coatings were prepared on pure titanium by micro-arc oxidation (MAO) in an electrolytic solution containing calcium chloride and calcium glycerophosphate due to its low-cost and high conductivity.SEM and XRD were adopted to investigate the microstructure and phase composition of the coatings. The coatings were formed using the bipolar pulse anodization under different calcium chloride concentration at Ca/P ratio, various voltages and process duration. The effect of CaCl2 concentration and anodization duration on the formation of MAO size and morphology has been studied. Pore diameter , oxide layer thickness and roughness of MAO coatings increased with increasing CaCl2concentration due to its high conductivity than no CaCl2 addition. Above 0.03M CaCl2 concentration and 310V, the oxide layer thickness and roughness decreased owing to the probable separating. Perovskite and α-Ca3(PO)2 phase were found in oxide layers under above 280V condition, but hydroxyapatite phase was not found in the layer.