Surface effects in various bending-based test methods for measuring the elastic property of nanowires.
The size-dependent elastic property of nanowires induced by the surface effect is investigated by using the core-shell model. The overall effective elastic moduli of nanowires with regular polygonal cross-sections are unified into a simple and explicit relation. It is found that the effect of surface elasticity on the elastic moduli can be well characterized by two dimensionless material and geometric parameters with clear physical meaning. Finite element simulations demonstrate that the derived theoretical relation is applicable for all the vibration, bending, and buckling test methods for measuring the mechanical properties of nanowires. The analytical result is also validated by comparing it with relevant experimental measurements. This study is helpful not only for interpreting various phenomena associated with size-dependent mechanical properties of nanowires but also for developing and evaluating test techniques for material characterization at the nanoscale.
Zheng
Xiu-Peng
XP
AML, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, People's Republic of China.
Cao
Yan-Ping
YP
Li
Bo
B
Feng
Xi-Qiao
XQ
Wang
Gang-Feng
GF
D004548:Elasticity; D020342:Finite Element Analysis; D008422:Materials Testing; D015233:Models, Statistical; D008962:Models, Theoretical; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D013314:Stress, Mechanical; D013499:Surface Properties