本研究主要是結合同步X 光散射及小角度散射探討鋁銅合金的 析出相轉變及微結構演化的過程，進一步描繪出隨著溫度增加的過程 中，鋁銅合金析出相變化的細節，如：各析出相的成核或溶解的特徵 等。小角度X 光散射可以解讀鋁銅合金整體隨著溫度及時間改變的 過程中，析出相微結構變化的資訊，再藉由X 光散射圖譜記錄各析 出相的相變化演化對應溫度變化的相關資訊，根據這兩個實驗方式， 本論文觀察到鋁銅合金在因為提升溫度造成的析出相改變過程中，各 種詳細的微結構改變趨勢並量化其分析結果，從X 光散射得知的晶 格結構到小角度X 光散射解讀的奈米尺度下析出相形態學方面的演 變等，最後從各種材料微結構改變的趨勢中，進一步去判斷主要造成 鋁銅合金強化的原因。從本研究結果觀察到在使用熱處理增進鋁銅合 金強度方法中，強度貢獻最多，也就是最重要的主導因素為析出相的 相變化，而非析出相尺寸或是晶粒尺寸的改變。 An experimental investigation, combining synchrotron X-ray diffraction and small-angle scattering to study the microstructure evolution and phase transformation of the precipitation in an Al-Cu superalloy. Upon increasing the temperatures during precipitation process, the dissolution and the nucleation of different phases are characterized. The small-angle X-ray scattering profiles demonstrate the temporal behavior of structural evolution of the precipitates. The X-ray diffraction patterns records the spatial relationship of various precipitates during the phase transformation and reflect the phase transformation of the precipitates during the heating. The present study provides the insight of the phase transformation structural characteristics in the Al-Cu system from the lattice structure to the nano-scale morphological geometry simultaneously. Finally, determine the main structure factor improve the strength of Al-Cu alloy from these microstructure evolution information with temperature. Observe from the results of this study, the main structure factor enhance the strength of Al-Cu alloy is precipitation phase transition.
