微弧氧化(Plasma electrolytic oxidation, PEO)技術是涉及電化學反應、電漿化學與熱擴散效應共同作用，藉電解液的調配、工作時間及電源參數的控制，能快速成形具目標相結構之氧化膜鍍層於輕金屬鎂、鋁、鈦上，屬近期表面改質新興技術之一。故本研究利用電源供應之電性參數於鎂合金上發生弱工作區(Soft regime)現象，此效應控制膜層品質，因此發展出於鎂合金材料上藉由添加奈米粒子氧化鋯，以及觀察添加後弱工作區現象對鍍膜反應之影響研究。本實驗選用當今探討弱工作區現象中較少討論的基材-鎂合金微弧氧化鍍製材料，研究弱工作區於添加奈米粒子後之影響與鍍膜相互關係。研究首先達成微弧氧化弱工作區電源參數之最佳化，確立了弱工作區現象需在CR < 1以及調控適當的電源參數方能形成。

Plasma Electrolytic Oxidation (PEO) is an electrochemical, high voltage plasma-assisted oxidation, environmentally-friendly aqueous electrolyte to oxidize the light metal surfaces to form ceramic oxide coatings which applied to aluminum, titanium, and magnesium metal or alloys. It is one of new applied today as manufacturing wet surface process. However, using pulse bipolar plasma electrolytic oxidation technology were coated on magnesium alloys AZ91D employing electrolytes with/without adding nano-scale ZrO2 powder to produce zirconia ceramic thick films. Under a constant current mode can obtain a special voltage-drop behavior, named soft regime, in this study which is adjusting positive/negative current ratio (CR) through power supply. On the other hand, when working in this regime, the density of the oxide layer increases and the bonding of substrate to coating layer can be enhanced as well.

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