本研究使用 Inconel 617 鎳基合金來探討應變速率效應。Inconel 617是第四代先進核反應系統的熱交換器候選材料之一。這個實驗在美國橡樹嶺國家實驗室進行，利用VULCAN在高能量的spallation中子源和搭配新開發動態讀取軟體來建立一個連續即時量測的環境。一般來說，楊氏模數會隨應變速率增快而增加。此實驗發現不同微觀模數會隨應變速率改變。在微觀下，{111}晶面的模數和巨觀的模數改變趨勢相反。我們搭配分子模擬及電子穿透顯微鏡來比較觀測到的應變速率效應。Inconel 617 is a structural-material candidate for the intermediate heat exchanger used in the Generation IV Reactor Power Plant. It is important to investigate its strain rate effect. We use both the high-flux neutrons at the Spallation Neutron Source and the novel data acquisition with reduction technique at the VULCAN Engineering Diffractometer to create in-situ experimental environment. Upon different strain rates, a change in the lattice modulus was discovered. In general, the greater Young’s moduli are typically in proportional to the bulk strain rate. The trend of the lattice-modulus transition is opposite to the changes of bulk modulus as a function of the strain rates. We also apply molecular dynamics (MD) simulation and transmission electron microscopy (TEM) to compare the measured strain rate effect.
