Effects of heat treatment on the compressive properties of AZ91 Mg foam

The compressive properties of a T6 heat-treated AZ91 Mg foam are compared with those of as-cast foam. The plateau stress of the foam was not increased by the standard T6 heat treatment. Microstructural observation revealed that the precipitates were rather large in the heat-treated foam, suggesting that the heat treatment applied in the case of the bulk materials is not necessarily suitable for these cellular materials. However, the densification strain of the heat-treated foam was the same as that of the as-cast foam. Therefore, it is suggested that the densification strain of the foam is independent of the microstructure of the cell edge solids.