Electrodeposition of nano-Cu, Ni and binary Ni/Cu into nano-porous AAO layer for high-efficiency black spectrally selective coating

Bulletin of the National Research Centre

Table 6 Measurements of surface hardness after electrolytic coloring of Al samples

Sample	Anodization time (min)	HB (Brinell hardness number)
Al blank	–	47
Al Anodized	30	52
Al colored by Ni	30	53
Al colored by mixture Ni and Cu	30	51
Al colored by Cu	20	50
Al colored by Cu	30	51
Al colored by Cu	60	54