本論文主要使用材料萬能試驗機在室溫(25℃)以及高溫下(450℃與
900℃)研究Ti-12Mo-6Zr-2Fe 生醫鈦合金準靜態壓縮特性，並探討其機械性質及微觀結構。準靜態壓縮試驗所選用應變速率分別為0.001s-1、0.01s-1 和1s-1，而實驗溫度則設定為25°C、450°C、900°C。壓縮測試後再藉由光學顯微鏡(OM)及穿透式電子顯微鏡(TEM)觀察變形前後之內部顯微結構，藉此分析在不同的溫度及應變速率下材料塑變行為與微觀結構之相關性。最後利用構成方程式模擬巨觀特性。
實驗結果指出，在相同的溫度條件下Ti-12Mo-6Zr-2Fe，材料之塑流
應力、加工硬化率、應變速率敏感性係數以及理論溫升量會隨著應變速率的增加而上升；而在相同應變速率的條件下，熱活化體積會隨溫度上升而下降，塑流應力、加工硬化率、應變速率敏感性係數及理論溫升量會隨溫度下降而上升。模擬結果顯示Ti-12Mo-6Zr-2Fe 合金，可藉由CombinedJohnson-Cook & Zerilli-Armstrong 構成方程式精確的描述其塑性變形行為。
在材料微觀性質方面，透過光學顯微鏡顯示出本材料為介穩態之β
相之鈦合金，材料在450°C 之金相圖有析出物的產生，而900°C 因超過
本材料β轉換溫度，析出物重新溶解至β相，顯示為純β相之鈦合金；在
穿透式電子顯微鏡觀察下，可發現差排密度隨著溫度上升而下降，隨著應變速率上升而上升。最後結合巨觀與微觀之結果顯示，Bailey-Hirsch 方程式可準確描述塑流應力值與差排密度之關係。

In this thesis, the quasi-static compression properties and microstructure of the Ti-12Mo-6Zr-2Fe biomedical titanium alloy were studied at different temperatures of
25 °C, 450 °C, 900 °C and low strain rate from 0.000s-1 to 1s-1 using the universal testing machine. The high temperatures of 450° C, 900° C, were obtained by using
the deformation dilatometer.The results indicate that under the same temperature conditions, the flow stress, work hardening rate, strain rate sensitivity coefficient and theoretical temperature rise of Ti-12Mo-6Zr-2Fe, all increase with the increasing strain rate, but decrease with the
increasing temperature. However, the thermal activation volume and the activation
energy have completely opposite tendency. The Combined Johnson-Cook & Zerilli-
Armstrong model on Ti-12Mo-6Zr-2F can be used to describe the deformation
behavior.
The optical microstructure shows that the Ti-12Mo-6Zr-2Fe has a pure β type
titanium alloy at room temperature. The appear on the microstructure as the temperature is increased precipitated fine alpha and omega phases. However, as the
temperature were higher than the beta transus temperature of 754°C, a pure β type titanium alloy is found. The transmission electron microscop observations indicate
that the dislocation density decreases as the temperature is increased or the strain rate is decreased. The relationship between the stress and the dislocation density can be explained by using the Bailey-Hirsch equation accurately.

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