accuracy of the 720 rule
I have logged dozens of anodizing runs using different alloys, different current densities and different target oxide thicknesses. For each run, I calculated the run time using
Time(minutes) = CD/(thickness * 720)
After each process I measure the oxide using a calibrated isoscope, and have found that the oxide is typically +-7% of the target oxide thickness. So my question(s) is/are:
1. Just how accuate and reliable is the 720 rule?
2. What are some factors that will affect the accuracy? bath temperature? conductivity? Rectifier ripple?
thanks
kevin
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