Questions on Fibergeek's Anodization Curves 1 of 3

[scocklin]

I have been reading through your anodization curves and trying to understand how they work. I first had to look up the properties of each of the alloys (basics) and found that the purity of aluminum starts with 1100 being 99% Al down to 7075 being 90% Al. I think this all corresponds to your chart. The electric resistivity starts at 30 for the 1100 and ends at 52 for 7075. I need your help in understanding this but I assume looking at the properties this is a measurement of ohms. The properties read for 7075 (10 to the minus ninth ohms-m) so 1100 alloy has the least resistance and 7075 has the most?

So looking at your first set of curves I was able to determine that the alloys follow their properties of resistance.

What I need help with is understanding bulk resistance (OSF) could you give me an example using numbers as to how you determine OSF?

I think I understand the relationship between electrolyte concentration, temperature and current density. Does this mean if you start a run with an unknown alloy say at 4.5 ASF using a CC PS and you immediately notice a decrease in voltage indicating a difficult alloy can you raise the current during the run to correspond to 6 ASF or 12 ASF? Can you change the current density during a run?

After I completely understand this set of curves I’ll have more questions concerning the second and third set. Thanks again.

[Fibergeek]

I'll post a numerical example tomorrow. The math is very simple.