Processing, properties and coating of micro-porous syntactic foams

Micro porous syntactic foams were successfully produced by pressure-assisted infiltration of sintered borosilicate glass bubble structures with AlSi9Cu3 and ZnAl4Cul alloy melts. Specimens with densities as low as 1 g/cm(exp 3) for aluminium and 3 g/cm(exp 3) for zinc and good infiltration qualities could be obtained whereas tests with the magensium alloy MgA15Zn led to extensive reactions between the glass and the magnesium melt. Compression tests with aluminium matrix specimens showed that this material has a very high compression strength and behaves almost like an ideal crash energy absorber. It could be shown that due to its strictly closed and microscopic-scale porosity this kind of foams can be surface treated e.g. by copper-plating and chromatizing or by anodizing processes.