Metallic foams by PM Technology

Aluminium and Aluminium-based alloys have been foamed by using a special powder metallurgical route: After mixing the metal powder with a powdered foaming agent the mixture is compacted appropriately. During a subsequent heat-treatment at temperatures slightly above the respective melting temperature the semifinished product develops a highly porous structure porosity values of up to 90 percent have been obtained. Mechanical testing shows that metallic foams provide excellent ewnergy dissipation features, but on a much higher strength level as compared to foamed organic materials. Alluminium foam floads upon water due to its closed porosity. The conductivity of heat and sound vibration have also been measured. Relultant areas of application will be outlined.