Aspects of the reproducibility of mechanical properties in Al based foams

Abstract

Al foams have been manufactured via a PM route and compression tested. Testing has shown that density-properties relationships can be constructed which are then valid for the prediction of mechanical response for a sample of given density. The scatter in the density can also be used to predict, with reasonable confidence, the scatter in properties. Testing has shown that little or no difference in processing time can give rise to foams with significantly different densities and hence an undesirable, but nevertheless quantifiable and predictable, scatter in mechanical properties. This demonstrates the sensitivity of the very rapid foaming process and highlights the requirement for improving foam stability. The mechanical response of foams with similar densities is, however, reproducible suggesting that this is a more suitable way in which to control the process rather than by fixing the foaming time.