Table 4.

Comparison of energy absorption capacity of our samples with other ASFs.

Foam	ASF-I	ASF-II	Closed Cell Aluminum Foam [28]	ASF	ASF	ASF
Hollow sphere	C/C	C/C	No	expanded perlite particles	ceramic cenospheres W125	hollow ceramic microsphere
Sphere density (g/cm3)	0.16	0.25	/	0.18	0.7	0.6–0.8
Diameter	6.30 mm	6.36 mm	/	irregular shapeca. 4 mm	75 $\mathsf{\mu }\mathrm{m}$	15–75 $\mathsf{\mu }\mathrm{m}$
Aluminum matrix	Al alloy ZL101	Al alloy ZL101	multiple types Al alloy	Alalloy A356	commercial pure Al	commercial-purity Al and 7075-T6 Al alloy
Densification strain	0.6	0.6	0.6	0.5	0.5	0.55–0.6
Foam density (g/cm3)	1.14	1.21	0.2–0.6	1.02–1.06	2.2–2.4	1.4–1.66
Energy absorption per volume at densification (MJ/m3)	30.1	34.9	1–10	11.9–23.6	26.0–34.9	55 (cp-Al, strain: 0.6) 80 (7075-T6, strain: 0.55)
Energy absorption per mass at densification (KJ/Kg)	26.4	28.8	/	11.3–22.3	11.6–12.7	39.3 (cp-Al) 48.2 (Alloy T6)