Determination of localized stress–strain behavior of fused silica: Inverse numerical analysis from nanoindentation test

Abstract

Because the localized mechanical properties of fused silica are unlikely to be obtained via conventional tensile testing, an inverse numerical analysis has been applied to deduce these properties using the load–displacement curve from nanoindentation testing. The mechanical properties were initially assumed, and the load–displacement curve was numerically simulated using three-dimensional elastic–plastic finite element analysis. The mechanical properties were adjusted until the numerical curve corresponded to the experimental curve, and then the localized mechanical properties in the vicinity of an indentation could be estimated. Unfortunately, the inverse numerical analysis requires time-consuming numerical calculation, involving many repetitions, by experienced researchers. In the present work, the influence of mechanical properties on the nanoindentation parameters of fused silica was evaluated, and the systematical adjustment of mechanical properties to obtain a satisfactory load–displacement curve has been proposed. It is considered that this procedure can be applied for the evaluation of localized stress–strain behavior of fused silica.