Effect of cooling rate on structure and mechanical behavior of glass by MD simulation

By using the molecular dynamics (MD) simulation method, we investigated the effect of cooling rate on structure and mechanical behavior under stress, including deformation and fracture, for a typical commercial window glass. An increased cooling rate reduced the degree of polymerization in the network structure of the glass. The structure in this case, was found to exhibit smaller rings and smaller bond angles. As a result, the glass cooled at a higher rate had a smaller Young's modulus and flowed more readily. This probably leads to faster stress relaxation and less tendency to crack, i.e., lower brittleness. The nano-structure and mechanical properties simulated are discussed in comparison with actual experimental data. (C) 2004 Elsevier B.V. All rights reserved.