鋁合金的活性高在溶解過程或澆鑄轉湯、充模時容易形成或捲入氧化膜，這對鋁合金的機械性質或表面陽極處理品質會有顯著的影響。工程人員深知欲獲得高品質的鑄錠或鑄件必須提高清淨度、減少氧化膜或介在物顆粒的殘留。在一系列的氧化診斷以及對機械性質（疲勞壽命）的影響之研究後，發覺相關文獻和研究等對氧化膜的分解、合成反應等缺乏明確的實驗資料和學理說明。本研究延續以往的研究成果，擬以二年的時間探討鑄造鋁合金中氧化膜的分解和合成反應等。溶解實驗時以氬氣保護試塊避免氧化，以高純度鋁為基材，並分別在基材上施以加熱或蒸度形成氧化鋁膜，再將基材和鋁合金塊以三明治方式結合併加熱溶解。實驗結果配合超音波檢測和剖面觀察(SEM, EDAX and EPMA)不同條件下氧化膜的分解和合成反應等。實驗成果配合電腦畫圖分析晶格孔隙，分析鋁或矽離子的可能擴散路徑，並討論矽附著於氧化鋁的機制，氧化鋁和鎂作用形成spinel 的過程。 Aluminum alloys are very reactive forming oxide film during melting and pouring or filling of molten aluminum alloys into mold cavity. The trapped-in oxide film tends to reduce the fatigue life cycles of cycles of castings and to deteriorate the surface quality of anodized parts. Most engineers realize that for assuring the quality of aluminum alloy castings, the cleanness of the melt should be approach first and then reduce the entrapping oxide film and inclusion particles. There are few research works focus on the decomposition and reaction of oxide film in the melt and casting. All of the mechanism or process of decomposition and reaction are not clear due to lacking of information or experimental data available for discussion. This study plans to provide experimental results for showing these decomposition and reaction of oxide film in the melt and casting in two year』s work. The specimen cubes will be prepared from high purity Al, which is going to be heated to thermal oxide film or to get a deposition oxide layer on the cube. This cube would bond with different Al alloy and melt for different time. The solidified cake will be inspected by ultrasonic testing for determining the critical heating for sealing the interface of cube and Al alloy specimen. SEM, EDAX and EPMA will be used to observe the cross section of fused cake and to identify the decomposition and reaction of oxide film in the casting. The lattice structure of oxides and will be analyzed by computer graphic technique to compute the pore size existed in an unit lattice and the possible diffusion paths with alumina. The discussion will be extended to cover the nucleation of silicon on the surface of alumnina and the reaction process for forming spinel. 研究期間：9308 ~ 9407
