Modeling of Glass Fiber with Surface Cracks—A Molecular Dynamics Simulation Study

Abstract

Theoretical strength of glass fiber is much higher than the experimental values. It is believed that nano-meter size surface cracks, which are developed on the fiber surface during manufacturing and later on handling, deteriorate fiber strength. In the paper, effects of surface crack on the mechanical properties (modulus and strength) of glass fiber are studied through reactive all-atom molecular dynamics (MD) simulations. Surface cracks of different length are created by deleting atoms. Two types of reactive force fields – ReaxFF and Tersoff, are considered to assess their accuracy and computational expense. Simulation results indicate that surface cracks have no effect on glass fiber modulus, however, fiber strength is significantly affected by surface crack. Presence of surface cracks reduces fiber strength. With the increase in crack length, strength decreases and MD derived strength-crack length response is in good agreement with theoretical prediction.