Effect of heat treatment on the impact response of aluminum foam with consideration of statistical analysis

In this paper, the effect of heat treatment on the impact behavior of A356 aluminum alloy foams reinforced by SiC particles was studied and new results was generated. The foam was manufactured by direct foaming of melts with blowing agent CaCO3. A number of foam specimens were processed by T6 aging treatment. The drop-weight impact test with a hemispherical striker tip and velocity of 6.70 m/s was carried out on five untreated foam specimens and five heat-treated foam specimens, and the load versus time history data was obtained. The obtained impact response of A356/SiCp composite foam includes three stages: an elastic region, a plateau of load region and complete failure region. In plateau region, the plastic deformations can be tolerated by the foam at nearly constant load. The small amounts of standard deviation and coefficient of variation (for different parameters) obtained from statistical analysis of experimental data indicates the reliance on the results for quantitative analysis of them. The measurements showed that heat treating of Al foam results in an increase of the plateau load level and energy absorption capacity of the foam with 48.1% and 40.3% increase respectively. The length of plateau region is also decreased due to heat treatment. Regarding the significant improvement of mechanical properties of the foam and increase of its impact strength, the heat treatment after foam casting can be considered as a suitable approach for various industrial applications of aluminum foam.