Mesoscale polycrystal calculations of damage in spallation in metals

Los Alamos National Laboratory, Los Alamos, NM 87545, USA

Abstract

The goal of this project is to produce a damage model forspallation in metals informed by the polycrystalline grain structure at themesoscale. Earlier damage models addressed the continuum macroscale in whichthese effects were averaged out. In this work we focus on cross sectionsfrom recovered samples examined with EBSD (electron backscattereddiffraction), which reveal crystal grain orientations and voids. We seek tounderstand the loading histories of specific sample regions by meshing upthe crystal grain structure of these regions and simulating the stress,strain, and damage histories in our hydrocode, FLAG. The stresses and strainhistories are the fundamental drivers of damage and must be calculated. Thecalculated final damage structures are compared with those from therecovered samples to validate the simulations.