Result: Multiscale modelling methods and the software for the analysis of the Micro-FAST process

Expected Impact/Targeted User Groups: First multiscale modelling technique for the modelling of a powder-metallurgy process which will substantially enhance process understanding and process control

The multi-scale model utilises a representative volume element (RVE) of the powder particles in a periodic arrangement with given periodic boundary conditions. The sintering process is simulated by applying a simultaneous pressure and direct current in addition to contact and a diffusion bonding or welding/fusion criteria, depending upon the temperature, at the surfaces. The boundary conditions on the RVE are obtained from e.g. a macro-scale finite element simulation of a real component, allowing different regions of interest to be studied using the RVE, as indicated in the diagram. The results allow the bonding state to be predicted throughout the compaction history (as a function of stress state, temperature and time) until full densification. The input parameters can then be varied appropriately so as to maintain a suitable temperature throughout the microstructure, thus effectively contributing to the design of the final micro-formed component. Predictions can be used to optimise MicroFAST machine parameters.