Mechanical Property Evaluation on the Bending and Compressing Behaviour of Nano-beam
Q. S. Bai, X. He, X. Q. Zhang, R. Q. Shen and Y. C. Liang
Journal of Wuhan University of Technology -- Materials Science Edition, 31, 903-906 (2016).
ABSTRACT
Based on quasicontinuum (QC) multiscale simulation method, a series of
simulation models were set up for bending and compressing rod-shaped
microstructure of single crystal Cu. The effects of structural parameters on
typical mechanical properties were analyzed, such as elastic modulus, elastic
limit, yield strength, and Poisson's ratio. According to the analysis of
displacement, inner stress and strain energy, the mechanisms of deformation and
failure were also revealed. The experimental result shows that the mechanical
properties exhibit obvious size effect during the bending and compression
process. In the bending simulation, when the span-thickness ratio is more than
10, the elastic modulus rises slightly with the increase of strain. And the
smaller the beam is, the faster the elastic modulus grows. Meanwhile, when the
span-thickness ratio keeps constant the elastic modulus will decrease with the
growth of the beam sizes. However, in the compression model, the size effect on
Poisson's ratio is not remarkable. The dimensional change in one direction
cannot influence the mechanical parameters greatly. Mechanical twins and
dislocation contribute to the compression behaviour greatly. Meanwhile, the
stress concentration can also be found in the inner partial area and the strain
energy decreases abruptly after the crush of beam microstructure.