本研究以即時中子繞射，研究鎳基超合金Inconel617的高溫疲勞行為。比較室溫、600˚C及850˚C下，疲勞循環應力加載所造成的結構改變。並藉由單軸拉伸實驗結果，比較不同巨觀形變模式所帶來的微結構如晶粒大小及差排衍生的變化。根據這兩個實驗的比較，本論文觀察到巨觀蠕變曲線改變趨勢依環境溫度而異，各溫度下不同形變方式所量到的中子數據也反應出不同的微觀特徵。比較參考文獻，本研究推論造成蠕變不同階段的機制可由中子繞射實驗偵測得到。本研究進一步歸納中子數據特徵，比對典型蠕變曲線中三階段不同的蠕變機制。;Abstract We investigate high temperature creep-fatigue properties of nickel-based superalloy, Inconel 617, by in-situ neutron-diffraction. We examined the microstructure subjected to monotonic and cyclic tensile loading under room temperature, 600˚C and 850˚C, respectively. The variations in microstructure caused by different deformation modes are compared. The trends in macroscopic creep curves subjected to different environmental temperatures show different features. Comparing to classic deformation map, we conclude that different creep stages on this materials is revisited. It is concluded that the main contribution of the increase in creep speed of tertiary creep is due to the increase of dislocation density, but not the variation of the lattice strain.
