Anodisation of Aluminium Alloys by Micro-Capillary Technique as a Tool for Reliable, Cost-Efficient, and Quick Process Parameter Determination

Table 2

Film thickness calculated by Faraday’s law (on pure Al), film thickness according to colour, film thickness estimated by ellipsometry, film thickness measured on cross sections (all on EN AW-7075 T73), O/Al ratio according to the film/substrate contribution calculated using the EDS spectra, and O/Al ratio derived from EDS analysis as a function of the anodisation potential (Ag/AgCl (3 M KCl)).

Film	(V)	(nm)	(nm)	(nm)	(nm)	O/Al ratio calculated	O/Al ratio measured
1 (Figure 7(a))	0.3	150	~50			0.05
2 (Figure 7(c))	1.8	205	~100			0.46
3 (Figure 7(e))	3.8	275	~200			1.12
4 (Figure 7(g))	10.0	745	~500			—