本文主要是利用材料萬能試驗機研究 316LVM 不銹鋼在不同晶粒尺寸及應變速率之準靜態壓縮特性與微觀結構，測試晶粒尺寸分別為32μm和64μm試件，而應變速率則設定為0.001 s−1、0.01 s−1和0.1 s−1，以探討晶粒尺寸及應變速率在準靜態塑變行為及微觀結構上之效應。
結果顯示 316LVM 不銹鋼的機械性質，會隨著晶粒尺寸和應變速率的不同而有些微差異；在相同晶粒尺寸下，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著應變速率的增加而上升；而當相同應變速率時，晶粒尺寸較小者，其塑流應力、加工硬化率、應變速率敏感性係數及理論溫升量的值較大，而熱活化體積則呈現相反的趨勢。
應力-應變特性可藉由 Combined Johnson-Cook & Zerilli-Armstrong 構成方程式，精確的描述 316LVM 不銹鋼的塑性變形行為與其整體趨勢。
在材料微觀性質方面，利用 OM 及 TEM 進行微觀結構的觀察，以解析巨觀特性與微觀結構兩者間之關連性。光學顯微鏡可觀察 316LVM 不銹鋼之金相結構，並使用 Hall-Petch 理論來驗證晶粒尺寸效應在準靜態壓縮下帶來的影響，同時透過實驗數據與理論計算分析其材料特性，以瞭解不同晶粒尺寸及應變速率對準靜態壓縮變形行為之影響。經由穿透式電子顯微鏡觀察下則可發現差排密度隨著應變速率上升而上升、晶粒尺寸較小之條件差排密度相較之下稍大，其中差排密度與塑流應力之關係可藉由 Bailey-Hirsch type 關係式來定量描述。

The purpose of this study is to investigate the effects of grain size and strain rate on the quasi-static deformation behaviour of biomedical 316LVM stainless steel by using compression tests.The tests were performed at room temperature under constant strain rates of 0.001s-1, 0.01s-1, 0.1s-1 at the different grain size of 32μm and 64μm, using the compression test. The results indicate that mechanical properties of 316LVM stainless steel are sensitive to strain rate and grain size. At the constant grain size, flow stress, work hardening rate and strain rate sensitivity all increase, but the thermal activation volume decreases with the increasing strain rate. However, at the constant strain rate, flow stress, work hardening rate, and strain rate sensitivity decrease but the thermal activation volume increases with the increasing grain size. A Combined Johnson-Cook & Zerilli-Armstrong constitutive equation is used to describe the quasi-static deformation behaviour of boimedical 316LVM stainless steel under tested conditions. Microscope (OM) observations reveal the the compressed grain size is increased as compared to the original grain size. With the increasing strain rate, the compressed grain size became more bigger. Furthermore, Transmission Electron Microscope (TEM) observationsshow the dislocation density increases with the increasing strain rate, but decreases with the increasing grain size. The relationship between the dislocation density and the stress can be expressed using the Bailey-Hirsch equation.

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