本論文主要透過霍普金森高速撞擊試驗機及高溫裝置，探討高熵超合金(Al10Ti0.5Cr7Co17Ni60Nb2Mo2W1.5)在溫度25℃、800℃以及應變速率2200 s-1、3400 s-1、5000 s-1、6200 s-1之條件下之巨觀機械性質，另外透過OM、TEM觀察微觀結構，綜合兩者以了解溫度與應變速率對材料的塑性變形行為及微觀結構的影響。
實驗結果顯示，高熵超合金(Al10Ti0.5Cr7Co17Ni60Nb2Mo2W1.5)在相同溫度條件下，塑流應力值、加工硬化率、應變速率敏感性係數及溫度敏感性係數皆隨應變速率的上升而上升，而熱活化體積則隨應變速率的上升而下降。但隨著應變量的提升，在應變速率5000 s-1及6200 s-1條件下，應變速率敏感性係數隨應變量上升而減少，熱活化體積隨應變量上升而增加，與應變速率2200 s-1及3400 s-1條件趨勢相反；在相同應變速率條件下，塑流應力值、加工硬化率、應變速率敏感性係數隨溫度上升而下降，熱活化體積隨溫度上升而上升。最後，引入Zerilli-Armstrong 模型來預測合金在不同溫度及應變速率條件下之塑性變形行為。
OM觀察中，相同溫度下，觀察到的滑移線隨應變速率上升而上升；相同應變速率下，滑移線數量隨溫度上升而下降。TEM觀察中，差排密度隨應變速率的上升而上升，隨溫度上升而下降；差排胞尺寸隨應變速率上升而縮小，隨溫度上升而增大。最後結合微觀及巨觀性質，可以得之差排密度、差排胞尺寸與塑流應力值呈線性關係。

In this study, dynamic impact response and microstructural evolution of High Entropy Superalloy (Al10Ti0.5Cr7Co17Ni60Nb2Mo2W1.5) under high strain rates from 2200 s-1 to 6200 s-1 and various temperatures from 25℃ to 800℃ were investigated by using split-Hopkinson pressure bar.
The results show that the mechanical properties are greatly affected by strain rates and temperatures. It is found that the flow stress, work hardening rate, strain rate sensitivity and temperature sensitivity increase, but the thermal activation volume decrease with the increasing strain rate. However, under the strain rate 5000s-1 and 6200s-1, strain rate sensitivity decreases, and the thermal activation volume increases with the increasing strain. At a constant strain rate, the flow stress, work hardening rate and strain rate sensitivity decrease, but the thermal activation volume increase with the rising temperature. Finally, the Zerilli-Armstrong model is used to describe the plastic deformation behavior of High Entropy Superalloy (Al10Ti0.5Cr7Co17Ni60Nb2Mo2W1.5) under different strain rates and temperatures.
Optical microscope observations show that the amount of slip lines increase with increasing strain rate and decreasing temperature. Transmission electron microscope observations show that dislocation density increases, but dislocation cell size has the opposite result with increasing strain rate and decreasing temperature. Finally, it is found that the relation among stress, dislocation density and dislocation cell size is linear.

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