Nat Mater. 2010 Mar;9(3):215-9. doi: 10.1038/nmat2622. Epub 2010 Feb 7.
Amorphous metallic alloys, or metallic glasses, are lucrative engineering materials owing to their superior mechanical properties such as high strength and large elastic strain. However, their main drawback is their propensity for highly catastrophic failure through rapid shear banding, significantly undercutting their structural applications. Here, we show that when reduced to 100 nm, Zr-based metallic glass nanopillars attain ceramic-like strengths (2.25 GPa) and metal-like ductility (25%) simultaneously. We report separate and distinct critical sizes for maximum strength and for the brittle-to-ductile transition, thereby demonstrating that strength and ability to carry plasticity are decoupled at the nanoscale. A phenomenological model for size dependence and brittle-to-homogeneous deformation is provided.
非晶态金属合金，或金属玻璃，是具有优势的工程材料，因为它们具有高强度和大弹性应变等优异的机械性能。然而，它们的主要缺点是容易发生灾难性的失效，通过快速的剪切带形成，这大大限制了它们在结构中的应用。在这里，我们展示了当尺寸减小到 100nm 时，基于 Zr 的金属玻璃纳米柱同时达到了陶瓷般的强度（2.25GPa）和金属般的延展性（25%）。我们报告了最大强度和从脆性到韧性转变的临界尺寸是分开的和不同的，从而证明了在纳米尺度上强度和承载塑性的能力是解耦的。提供了一个关于尺寸依赖性和从脆性到均匀变形的现象学模型。
