Thermag VII Torino Italy ELICiT EU PROJECT September 14th. 2016

Thermag VII Torino Italy ELICiT EU PROJECT September 14th. 2016

Metal Foams: Research and Applications Prof. Stefano Guarino University of Rome ‘Niccolò Cusano’ Via don Carlo Gnocchi, 3 – 00166 Rome stefano.guarino@unicusano.it

Metal Foams Characteristics: low density; high specific strength; The cellular metals, closed and open cell structure, are gaining great interest because of the many potential applications in various technology domains. They combine in a single element very attractive properties. Characteristics: low density; high specific strength; resilience (impact protection); absorption of mechanical energy; interesting heat transfer properties (open cell structures); sound absorption.

Manufacturing Processes

Manufacturing Processes

Applications

Foaming processes for open-cell systems: Replication of polymer patterns Preparation of pattern - Material: Refractory and resistant to the metal's melting temperature; - After infiltration there must be an open path for the evacuation of the pattern. Possible Patterns Continuous refractory (space holder for replication); Discontinuous refractory (sand pellets foundry); Burnable (polystyrene and resin); Leachable (dissolution processes).

Space holder for replication, polymer patterns

Foaming processes for open-cell systems: Replication of polymer patterns Infiltration It can be made in gravity or under the action of an additional pressure. The necessary pressure, when starting the infiltration can be assessed by this empirical law: P = 16 f /(1-f)D - 0.09 MPa f volume of solid fraction D characteristic diameter (Cell)

Foaming processes for open-cell systems: Replication of polymer patterns Removal of the pattern It can be done by means of water-jet at high pressure with assistance (or not) of ultrasound to chip away the sand particles; In the case of polymer patterns these can be removed by combustion in air; As regards the processes for dissolution the pattern is removed by exploiting the solubility in water.

Foaming processes for open-cell systems: Replication of polymer patterns

Open cell foams: Thermal Exchange In the last years, porous material, such as metal foams with open cells has been the subject of studies in thermal management. Those materials can provide significant advantages in term of heat exchange. In fact high ratio surface/volume and the porous structure provide thermal coefficient extremely high.

Open cell foams: Pressure drops

A summary of progress towards objectives MAIN TASKS Evaluation of the current state of the art Acquisition of all the necessary input data from other Partners Innovative solutions to enhance the performances of the heat transfer devices

Brazing Process Comparison between two specimens coated for 10 min but at different currents 10mA 20mA

Brazing Process Brazing process parameter investigation Brazing tests Atmosphere: in air Temperature: ~ 200°C Brazing alloy: 60% Sn 40%Pb Copper pipe brazed in a sandwich of metal foams

EXPERIMENTAL SETUP AND TESTING The experimental setup has been conceived for the purpose of determining the performance of the heat exchanger. In particular the fluid pressure drop along the heat exchanger and the heat dissipated into the environment are investigated Details of the used instrument

Thank You. Prof. Stefano Guarino stefano. guarino@unicusano Thank You! Prof. Stefano Guarino stefano.guarino@unicusano.it elicit-project.eu #MagneticCooling