论文标题
通过互补压力和结构调制,在金属眼镜中的恢复活力工程
Rejuvenation engineering in metallic glasses by complementary stress and structure modulation
论文作者
论文摘要
剩余的压力工程非常广泛地用于设计新的高级轻质材料。对于金属眼镜,注意力一直是结构变化和复兴过程。高能扫描X射线衍射应变图揭示了在三轴压缩下变形后金属玻璃的弹性波动。微调硬度映射暗示压缩后的竞争性加工机制,并进一步揭示了压力和结构调制的互补作用。透射电子显微镜证明,在室温变形下的结构调制与剪切带的形成有关,剪切带的形成与弹性异质性的分布密切相关。分子动力学模拟提供了对缺口金属玻璃中复杂的剪切带活性以及应变/应力异质性中相关波动的原子理解。因此,将来应将重点放在压力工程和弹性异质性上,结构调制可能允许设计具有增强延展性和应变硬化能力的金属玻璃。
Residual stress engineering is very widely used in the design of new advanced lightweight materials. For metallic glasses the attention has been on structural changes and rejuvenation processes. High energy scanning X-ray diffraction strain mapping reveals large elastic fluctuations in metallic glasses after deformation under triaxial compression. Microindentation hardness mapping hints to a competing hardening-softening mechanism after compression and further reveals the complementary effects of stress and structure modulation. Transmission electron microscopy proves that structure modulation under room temperature deformation relates to the shear band formation that closely correlates to the distribution of elastic heterogeneities. Molecular dynamics simulations provide an atomistic understanding of the complex shear band activity in notched metallic glasses and the related fluctuations in the strain/stress heterogeneity. Thus, future focus should be given to stress engineering and elastic heterogeneity that together with structure modulation may allow to design metallic glasses with enhanced ductility and strain hardening ability.