Figure 2: Compressive stress-strain curves for hydride (F1, F3, F4, F11, and F12) and carbonate (F2 and F14) kinds of Al/Al-alloy foams processed with (F1–F3, F7, and F11) and without (F4, F8, F12, and F14) Ca additive: (a) Al-foams based on Al-7Si alloy (F3 and F4), Al-1Mg-0.6Si alloy (F7 and F8), Al-5Mg alloy (F9); (b) Al-foams based on pure Al (F1, F2) and Al-Zn-Mg alloy (F11, F12, and F14).