Modelling the microstructure and computing effective elastic properties of sand core materials

In this article we model sand core materials on the micro-meter scale, resolving individual sand grains and binding bridges, to obtain effective elastic moduli of the composite by computational homogenization, laying the foundations for investigating the strength properties of core blown parts with foundry applications. We analyze sand core materials on the basis of X-ray micro-computed tomography (µXRCT) images and extract a couple of sand grains from this volume image. These grains enter a packing algorithm which can generate granular packs with high packing fraction and incorporate sand grains with high complexity. Furnished with binder the resulting microstructures are investigated, deriving their effective elastic properties and studying the sensitivity w.r.t. the entering parameters. If a realistic range of elastic parameters of both sand grains and binder are plugged into the simulation, the agreement with experimentally obtained P-wave moduli is excellent.