近幾年來，由於工業快速發展，使得材料的耐用度成為很重要一門課題，因而衍生出利用三點彎曲來測試評估材料對於裂縫抵抗能力，做為材料在結構設計上之依據。 由於鋯基非晶質合金具有良好的玻璃形成能力及抗壓縮機械性質，且因添加矽元素於鋯基非晶質合金系統中可提升玻璃形成能力與其熱穩定性，因此本研究選用無矽及含矽之鋯基非晶質合金作為主要基材，同時本研究藉由傾倒式鑄造(Tilt-casting)及墜落式鑄造(Suction-casting)製程來製作Zr53Cu30Ni9Al8、Zr48Cu36Al8Ag8、(Zr53Cu30Ni9Al8)99.25Si0.75與(Zr48Cu36Al8Ag8)99.25Si0.75等鋯基系列塊狀合金，並依據ASTM E399規範之三點彎曲測試，來探討該系列合金之破裂韌性。 以傾倒式鑄造製備之非晶質試片，其破裂韌性較墜落式鑄造製備的試片來的高，若以鋯基與添加矽之鋯基非晶質合金來看，鋯基(Zr53Cu30Ni9Al8)合金具有最佳破裂韌性，其值約120 MPa?√m，相對另一鋯基(Zr48Cu36Al8Ag8)合金其值則降為68 MPa?√m。另外添加Si元素之鋯基，非晶質合金其破裂韌性值均較未添加Si的非晶質合金來的低， (Zr53Cu30Ni9Al8)99.25Si0.75) 及((Zr48Cu36Al8Ag8)99.25Si0.75)非晶質合金之破裂韌性值分別為107 MPa?√m及34.4 MPa?√m；本研究同時也探討塊狀金屬玻璃之破裂能量(Rupture energy)與浦松比(Poission?s ratio)、剪切模數(Shear modulus)及對應溫度之關係。其中Zr53Cu30Ni9Al8具有較高破裂韌性(K1C)、破裂能量(J)、浦松比(?，Poission?s ratio)、較低剪切模數(μ，Shear modulus)及彈性係數，其值分別為:120 MPa√m、155 kJm-2、0.373、30 GPa、83 GPa。 In recent years, due to the rapid development of industry, the endurance of materials becomes a major issue on each kinds of industrial product. Therefore, the evaluation of crack resistance ability by three-point bending test is applied as the reference of structure design. Zr-based bulk amorphous alloys (BAA) possess good engineering properties and its glass forming ability can be adjusted via minor-alloying of silicon element. Therefore, these two Zr53Cu30Ni9Al8 and Zr48Cu36Al8Ag8 Zr-based amorphous alloys are selected for this study. Both bulk amorphous alloys (BAA) plates were fabricated by tilt-casting and suction-casting. Then these bulk amorphous alloys (BAA) plates were followed ASTM E399 to machine into the three-point bending specimens for investigate their fracture toughness. Experimental results revealed that tilt-casting (Zr53Cu30Ni9Al8) specimen possess the best fracture toughness among all specimens in this study and reaches value about 120 MPa√m. On the other hand, the calculate fracture energy and Poisson’s ratio show same trend to prove tilt-casting Zr-53 owns the best mechanical properties.
