The DFG project “Mineral-Bound and Reusable Molding Materials for the Casting of Aluminum Components” (WE 5978/8-1) focuses on the use of ultra-high-performance concrete (UHPC) made from alkali-activated materials (AAM) under thermomechanical stress. The goal is to produce reusable molds for light metal casting. Due to their inherently lower chemical reactivity toward molten metals and their lower thermal conductivity compared to metal molds, AAMs offer the potential to enhance casting quality, improve process efficiency, and enable new applications in aluminum casting.

Among other things, the goal is to reduce reactivity and thermal conductivity compared to metallic molds. For specialized applications such as thin-walled components, low thermal conductivity of the mold is advantageous so that the molten material can completely fill the cavity before it solidifies.

A central focus of the research is understanding the relationship between the phase composition of the binder matrix and its evolution under cyclic thermal loading. To this end, the composition of the AAM-UHPC is specifically varied, and conclusions regarding the phase composition are drawn through phase analysis and microstructural investigations. These findings are then correlated with mechanical tests conducted after thermal loading.

Research is also being conducted to determine how the durability of mineral formwork materials can be improved. To this end, various aggregate sizes and fiber additives, among other things, are being tested. Mold filling simulations are compared with experimental data to determine the stress distribution during the casting process and to predict the service life of the concrete molds.

The project is a collaboration with the Chair of Foundry Engineering (Prof. Dr. Sebastian Müller) at Friedrich-Alexander University in Erlangen (FAU).