The Plastics Innovation Competence Center (PICC) increases its activities in the field of material multiscale modelling, allowing the development of innovative materials and reducing time and cost of processes. Siemens Industries Software supports the PICC by making available Multimechanics® engineering software for multiscale modelling. The software considers manufacturing variabilities, material imperfections, microstructure prior to and during failure, associated damage mechanisms, and microstructure optimization. The resulted simulations allow the investigation of material variability/versatility, optimization of operating conditions, mechanics, rheology and process cost efficiency.

The multiscale modelling consists of the following:
1) The material elastic moduli and overall linear-elastic behavior are evaluated through atomistic molecular dynamics simulations, where focus is put on variations in the chemistry, composition and molecular structure of components.
2) The mechanical information simulated as a function of material variability is used for parametrizing the microstructural model.
3) The results are postprocessed and conveyed into the meso- or macro-structural model which predicts the global response of the materials to imposition of mechanical deformation.
4) The methodology allows to account for interconnection of different detail levels. By coupling the different material scales into the same computation run, it is possible to model complex behaviors, such as progressive damage using solely physics-based models.

Nikolaos Lempesis, scientist assistant at PICC, notes: “We take advantage of the inherent flexibility of simulations by combining atomistic/molecular, coarse-grained mesoscopic and continuum rheology models to come up with multiscale modelling solutions. Examples of such endeavors include the simulation of powder mixing and granulation, ceramic injection molding, structure and mechanics of nanocomposites and dynamics of thermal processes. Our overarching goal is to use simulations intuitively to develop new, biofriendly materials part of a circular economy“.

Joël Kuster, HEIA-FR Professor, highlights: “Multiscale modelling allows us to broaden our simulation portfolio, particularly in the field of failure mechanisms in heterogenous material. A mission of SeSi institute is to develop robust and safe components. In this respect, considering real material microstructure allows us to transfer the specific properties of complex materials onto macroscopic parts and thus predict with greater accuracy the durability of complete mechanical structures.”

More information: N. Lempesis (Nikolaos.Lempesis@hefr.ch), J. Kuster (Joel.Kuster@hefr.ch)