R-wells,
Hows it going?
Peak voltage occurrs when coating growth and dissolution reach equilibrium. However if you stop anodizing at peak voltage, you have stopped too soon the majority of the time. This is because although the coating continues to grow, the pore size has started to get large enough to reduce resistance and drop voltage. If all conditions are optimum you will be able to slow dissolution to a point that will allow you to hit peak voltage at the end of your anodizing time or past that point. Decreasing tank temp will slow dissolution but will increase the value of peak voltage. Better circulation also slows dissolution by decreasing temps in the pores.
At 72* tank temp. I usually hit peak voltage 15-20 min. before time is up.
This was learned from Fibergeek and has been verified by my own anodizing.
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