title: Effect of surface stress on stress intensity factors of a nanoscale crack via double cantilever beam model.
abstract: This paper studies the influence of surface elasticity on crack growth for a nanoscale crack advance. A crack is modeled as a double cantilever beam with consideration of surface stress. Using the Euler-Bernoulli beam theory incorporating with surface effects, a governing equation of static bending is derived and bending solution of a cantilever nanowire is obtained for a concentrated force at the free end. Based on the viewpoint of energy balance, the elastic strain energy is given and energy release rate is determined. The influences of the Surface stress and the surface elasticity on crack growth are discussed. Obtained results indicate that consideration of the surface effects decreases stress intensity factors or energy release rates. The residual surface tension impedes propagation of a nanoscale crack and apparent fracture toughness of nanoscale materials is effectively enhanced.
authors: College of Aerospace Science and Engineering, National University of Defense Technology Changsha 410073, China.
authors: Hua
authors: H
authors: Wang
authors: Xianfang
authors: X
authors: Li
authors: Guojin
authors: G
authors: Tang
authors: Zhibin
authors: Z
authors: Shen
mesh_terms: D019245:Compressive Strength; D003198:Computer Simulation; D055119:Elastic Modulus; D004735:Energy Transfer; D008956:Models, Chemical; D008958:Models, Molecular; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D013314:Stress, Mechanical; D013500:Surface Tension; D013718:Tensile Strength