本研究主要目標是探討金屬玻璃基材所使用之鋯基金屬玻璃薄膜(Zr53Cu29Al12Ni6)，並改善其薄膜的附著力，從而提高金屬玻璃塊材之韌性。
在這項研究中，金屬玻璃薄膜退火後所量測得到之電阻率結果與在DSC分析中所測量出來之過冷液相區（ΔT），兩者都擁有一個類似的的範圍結果。且在鋯基金屬玻璃塊材濺鍍上，厚度為200 nm之鋯基金屬玻璃薄膜和數個nm之Ti黏著層，經由四點彎曲試驗後可發現其彎曲應力值從~2.2提高至~3.9GPa。所以當濺鍍鋯基金屬玻璃薄膜和黏著層時，其應力值會大幅度的增加 (增加約為原本值之77％)，彎曲韌性(toughness)亦巨幅增加至~20倍，且表面延伸率(surface strain)從未鍍膜的0%則增為12~14%，因而試片有塑性變形的產生。其中原因為在表面產生剪切帶時，張力的表面即會產生伸長的效應；剪切帶的數量隨塑性變形的增加而增加，其密度高達~36/mm2。隨後，在進一步形成一條主要之剪切帶或裂紋。
鋯基金屬玻璃薄膜，其擁有之高韌性以及高強度之性質，致使可以防止剪切帶的傳播，從而來提高其基材之韌性。鋯基金屬玻璃薄膜有良好的性質可以阻擋金屬玻璃基材所產生之多數微小的剪切帶，進而防止主要金屬玻璃基材之剪切帶的傳播來防範全面性的破裂，由此提高其金屬玻璃基材之韌性。

The primary objectives of this study are to investigate the use of the Zr-based metallic glass thin film (MGTF) as a promising coating film to enhance bending property of the bulk metallic glass substrate.
In this study, the annealing resistivity of Zr53Cu29Al12Ni6 glasses forming film in the supercooled liquid region (ΔT, SCLR) reveals a similar ΔT range to that of DSC result. The Zr-based BMG substrate was coated with 200 nm thickness Zr-based thin film and a few nanometer thick Ti buffer layer, and its maximum four-point bending stress was improved noticeably from ~2.2 to ~3.9 GPa, an increase of ~77%. The toughness and surface strain are also significantly improved ~20 folds and to 12~14%, respectively.
As a result, the occurrence of the shear bands on the tension surface can create surface offsets, which serve as potential crack-initiation sites. Subsequently, more primary, secondary and tertiary shear bands are formed to accommodate large bending strains. The shear bands are highly populated to ~36/ mm2 for the MGTF/Ti-coated BMG substrate. The high ductility and strength of MGTF can prevent the shear band formations which can enhance its bending property. The good ductility of the MGTF can be attributed to the multiplication of the shear bands in the substrate, which prevents a catastrophic failure by primary shear band formations and increases the ductility of the Zr-based BMG substrate.

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