Modelizing and manufacturing of metallic foams for multi-functional applications – FOAM

Open-cell metallic foams (aluminium, copper, steel) provide a high potential for multifunctional applications (weight reduction, crash resistance, heat exchange, vibration damping, …) in many industrial sectors (energy, transport, …). Production of these cellular materials by the economic metalcasting route would allow their large dissemination.
However their development is limited by technical obstacles : lack of knowledge about relationships between micro-geometry and functional macroscopic properties, non Beerian behaviour of some foundry foams (they get preferred radiation directions), complex modelling of the production process (transient flow in a 4 phases medium), difficulty in passing from a description of the infiltration process at the pore scale to the one of the component, absence of foundry specific rules to insure a metallurgical health of components containing foam.
The project FOAM aims at providing a structured framework for the metalcasting of foams to better understand them, to develop dedicated computational models and tools and to validate the economic advantages on demonstrators. The partners are acedemics: ECP, ARMINES, INSA of Lyon, IUSTI ; industrialists: TN International AREVA, HUTCHINSON, Carbone Lorraine, MOTA, the Solaire2G start-up and CTIF (coordinator).
The two main targeted applications are heat exchange and energy absorption in crash conditions for land or sea transport, renewable energies like photovoltaic solar energy or wind energy and nuclear energy.
The project which fits 3 axes of the Matepro call, will be conducted following a triple approach: scientific (fine modelling and characterization), technical (development of industry-specific tools) and pre-industrial (production and functional characterization of demonstrators).
Several models will be developed to simulate and understand the behaviour of foams under compression and crash conditions, in heat transfer applications (Lattice-Boltzmann method) and in the field of radiations. These models will be based on foam topologies reconstructed in 3D (iMorph) from CT scans. To validate the models, foam samples will be produced by the metalcasting route or by Selective Laser Melting and then will be characterized.
A fundamental work will be conducted to determinate "ab initio" the most efficient structures for each application. To achieve these structures industrially, the requirements of manufacturing by the metalcasting route will be taken into account. This knowledge will make it possible to carry out a technological jump and to propose “tailor-made” and low-cost materials.
Foundry-specific rules will be defined for pre-dimensioning the filling and feeding systems (risers). In parallel, a mathematical model will be developed in order to model the manufacturing process based on the infiltration of a preform (porous core) by molten metal. This model will make a fine dimensioning of the filling and feeding systems possible.
A tool for functional dimensioning will be developed as a toolbox. It will make it possible to predict the performances of a given foam according to its morphological parameters, to determine the best morphology to reach specifications, as well as to dimension the filling system of a part.
At last, demonstrators will be dimensioned according to the industrial needs, produced and tested functionally. A tool for evaluating the foundry cost will be developed and an estimate of the potential industrial market will be performed.
This project will lead to: a better understanding of the morphological metallic foams parameters influence on their functional performances; the development of predictive models related to the use and the manufacture of these cellular metals; the creation of industry-specific tools.
In medium term, this project will lead to the development of new industrial products with high energy/mechanical/electric performances, constituting technological jumps in particular for components downsizing.