Effect of Foaming Duration and Temperature on the Foamability Behaviour of AISi7Mg0.6 Sandwich

摘要

In this study, effects of foaming duration and temperature on the foamability behaviour of Al based sandwich foam have been investigated. Al foams having composition of AISi7Mg0.6 were produced between two commercial Al sheets. 0.8% TiH_2 powder was used as foaming agent. Blocks produced by powder metallurgy route were extruded before foaming. Extruded foamable precursor was placed between two 1 mm Al sheets and rolled before foaming. Al sandwich foams were produced at various foaming temperatures and for various foaming duration. Effects of foaming parameters on the pore size, pore shape, wall thickness, density and the linear expansion rate of the foam were investigated. Experimental results have shown that increasing foaming temperature after certain duration demolished the sandwich structure and pore morphology whereas, increased the linear expansion rate and decreased the density of foams.