Ir-Ni-Ta metallic glasses (MGs) exhibit an array of superior high-temperature properties, making them attractive for applications at high temperatures or in harsh environments. However, Ir-Ni-Ta bulk MGs are quite brittle and often fracture catastrophically even before plastic yielding, significantly undercutting their high-strength advantage. Here, we show that the Ir-Ni-Ta MGs are not intrinsically brittle, but rather malleable when the feature size is reduced to micro/nano-scales. All tested Ir-Ni-Ta MG micropillars with a diameter ranging from ~500 nm to ~5 µm display a large plastic strain above 25% (the maximum up to 35%), together with a yield strength up to 7 GPa, well exceeding the strength recorded in most metallic materials. The intrinsic shear stability of Ir-Ni-Ta MGs, as characterized by the normalized shear displacement during a shear event, is much larger than those malleable Zr- and Cu-based MGs. Our results suggest that Ir-Ni-Ta MGs are excellent candidates for micro/nanoscale structural applications used at high-temperature or extreme conditions.

Ir-Ni-Ta金屬玻璃具有一系列優異的高溫性能, 使其在高溫或惡劣環境下具有良好的應用前景. 然而, Ir-Ni-Ta塊體金屬玻璃非常脆, 甚至在塑性屈服之前就經常發生災難性斷裂, 這大大削弱了其高強度的優勢. 我們的研究表明Ir-Ni-Ta金屬玻璃本質上並不是脆性的, 當樣品尺寸減小到微/納米尺度時具有良好的延展性. 所有進行測試的Ir-NiTa金屬玻璃微柱(直徑在500 nm–5 µm之間)均顯示出大於25%的塑性應變(最大值高達35%), 同時它們的屈服強度最高可達7 GPa, 遠遠超過迄今為止所有金屬材料的強度記錄. Ir-Ni-Ta金屬玻璃的本征剪切穩定性用剪切帶在單個剪切事件中的歸一化剪切位移進行表徵, 遠大於具有良好延展性的Zr/Cu基金屬玻璃. 因此, Ir-Ni-Ta金屬玻璃可作為在高溫或極端條件下工作的微/納米器件的候選材料.