@article{Ma2023, 
author = {Lijun Ma and Lena Du and Shu Wang and Qing Wang and Shifeng Xue and Hanxing Zhu and Qian Liu},
title = {Dimension-dependent mechanical features of Au-nanocrystalline nanofilms},
year = {2023},
journal = {Nano Research},
volume = {16},
number = {12},
pages = {13400-13408},
keywords = {atomic force microscopy, numerical simulations, nanocrystalline Au nanobeams, full-spectrum mechanical properties},
url = {https://www.sciopen.com/article/10.1007/s12274-023-6091-2},
doi = {10.1007/s12274-023-6091-2},
abstract = {For metal nanofilms composed of nanocrystals, the multiple deformation mechanisms will coexist and bring unique and complex elastic-plastic and fracture mechanical properties. By successfully fabricating large quantities of uniform doubly-clamped suspended gold (Au) nanobeams with different thicknesses and nanograin sizes, we obtain full-spectrum mechanical features with statistical significance by combining atomic force microscopy (AFM) nanoindentation experiments, nonlinear theoretical model, and numerical simulations. The yield and breaking strengths of the Au nanobeams have a huge increase by nearly an order of magnitude compared with bulk Au and exhibit strong nonlinear effects, and the corresponding strong-yield ratio is up to 4, demonstrating extremely high strength reserve and vibration resistance. The strong-yield ratio gradually decreases with decreasing thickness, identifying a conversion of the failure type from ductile to brittle. Interestingly, the Hall–Petch relationship has been identified to be still valid at the nanoscale, and K in the equation reaches 4.8 Gpa·nm1/2, nearly twice of bulk nanocrystalline Au, which is ascribed to the coupling effect of nanocrystals and nanoscale thickness.}
}