Development of a foaming process for particulate reinforced aluminum melts

This paper reports on investigations by Hutte Klein-Reichenbach and LKR in the course of the development of a new processing technique for cellular aluminum, to produce net shape parts of foamed aluminum via the melt route by gas injection. The foaming depends on the interaction between the blowing gas, the ceramic particles, and the melt. The stabilization of the foam by different particle contents in interaction with air, oxygen and nitrogen as blowing gas has been investigated for some matrix alloys with respect to the processing parameters. The resulting cell structure is characterized by computed X-ray tomography, light optical and scanning electron, as well as high resolution Auger electron microscopy. The microstructure Of the cell walls is presented as well as the achieved pore size and the local mass density distribution.