本文主要是探討Ti-13Nb-13Zr生醫鈦合金在不同應變速率及溫度下之塑性變形行為與對應的差排結構及絕熱剪切破壞特性。利用壓縮式霍普金森桿撞擊試驗機及加熱裝置，分別於應變速率1000 s-1、2000 s-1、3000 s-1及實驗溫度25℃、650℃、800℃條件下，進行Ti-13Nb-13Zr合金之高速撞擊試驗，再利用(OM、SEM、TEM)對微觀結構進行分析。
實驗結果指出，Ti-13Nb-13Zr合金在相同溫度條件下，其塑流應力值會隨應變速率之增加而上升；在相同應變速率條件下，其塑流應力值會隨溫度之增加而下降，而應變速率敏感性係數則隨應變速率區間之增加而增加，隨溫度之增加而減少，溫度敏感性係數則隨應變速率上升或溫度降低而增加。藉由 Combine Johnson-Cook and Zerilli-Armstrong構成方程式，並加入理論溫升量修正，可精準的描述Ti-13Nb-13Zr合金於不同溫度及應變速率下的塑變行為。藉由光學顯微鏡觀測Ti-13Nb-13Zr合金，可知其α’麻田散鐵相含量及晶粒尺寸會隨著溫度與應變速率不同而有所改變。在掃描式電子顯微鏡分析上，可觀察到破壞面上不同區域會具有延性破壞組織如瘤狀物、韌窩形貌及脆性破壞組織如劈裂形貌。在穿透式電子顯微鏡則可觀測到差排密度會隨著應變速率上升和溫度降低而增加。而塑流應力值隨著差排密度、α’麻田散鐵相含量的增加及晶粒尺寸的降低有明顯增加的趨勢，其相互間的關聯性可進一步藉由一關係式，得出應力值與顯微結構之關係。

Dynamic impact response and microstructural characteristics of Ti-13Nb-13Zr alloy are investigated under strain rates ranging from 1×103 to 3×103 s−1 and different temperatures of 25ºC, 650ºC and 800ºC, respectively, using a compressive split-Hopkinson pressure bar. The results indicate that mechanical properties of Ti-13Nb-13Zr alloy are sensitive to temperature and strain rate. The flow stress, strain rate sensitivity and temperature sensitivity all increase with increasing strain rate, but decrease with increasing temperature. A Combined Johnson-Cook and Zerilli-Armstrong constitutive equation is used to describe the deformation behavior of Ti-13Nb-13Zr alloy under current tested conditions. Microstructural observations show that the dislocation density, α’ volume fraction and grain size are varied with strain rate and temperature. Based on the experimental results of mechanical properties and microstructural characteristics, it is found that the correlation between the dislocation density, α’ volume fraction, grain size and flow stress can be expressed using the general relation.

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