Ductile bulk metallic glass
Ductile bulk metallic glass
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DOI：
10.1103/physrevlett.93.255506
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发表时间：
2004-12-17
影响因子：
8.6
通讯作者：
Johnson, WL
中科院分区：
文献类型：
--
作者：
Schroers, J;Johnson, WL
我们报告了在弯曲和无侧限压缩载荷条件下在单片 Pt57.5Cu14.7Ni5.3P22.5 块状金属玻璃中测得的显着整体塑性的实验证据。测量到 20% 的塑性应变，这在金属玻璃中是前所未有的。此外，在弯曲 4 毫米厚的样品时，观察到永久变形和失效前超过 3% 的应变。迄今为止，还没有整体金属材料表现出如此高的强度、广泛的延展性和高弹性极限的组合。高塑性体现在 0.42 的高泊松比上，这会导致剪切带尖端延伸而不是引发裂纹。这导致了多个剪切带的形成，并且是观察到的大整体延展性和非常高的断裂韧性（大约 80 MPa m(-1/2)）的起源。
We report on experimental evidence of pronounced global plasticity measured in monolithic Pt57.5Cu14.7Ni5.3P22.5 bulk metallic glass under both bending and unconfined compression loading conditions. A plastic strain of 20% is measured, never before seen in metallic glasses. Also, permanent deformation and a strain exceeding 3% before failure is observed during bending of 4 mm thick samples. To date, no monolithic metallic material has exhibited such a combination of high strength, extensive ductility, and high elastic limit. The large plasticity is reflected in a high Poisson ratio of 0.42, which causes the tip of a shear band to extend rather than initiate a crack. This results in the formation of multiple shear bands and is the origin of the observed large global ductility and very high fracture toughness, approximately 80 MPa m(-1/2).