Modeling the creep properties of olivine by 2.5-dimensional dislocation dynamics simulations

摘要

In this work we performed 2.5-dimensional (2.5D) dislocation dynamics simulations coupling climb with the glide dislocation motion to model the creep behavior of olivine, one of the main component of the Earth's upper mantle. In particular, we present an application of this method to determine the creep strain rate in a material with high lattice resistance, such as olivine. We show that by including the climb mechanism we reach steady state creep conditions. Moreover, we find that a creep power law with a stress exponent close to 3 can be extracted from our simulations and we provide a model based on Orowan's law to predict the creep strain rates in the high temperature and low stress regime. The model presented is relevant to describe the plastic flow of olivine in the Earth's mantle deformation conditions and can be useful to derive the high temperature creep behavior of other materials.