UNI 6404-1969 P Chemical and electrochemical surface treatment. Measurement of local thickness of metal precipitates and oxide layers, supersedes UNI 4237. microscopic method
This unification concerns the microscopic method for measuring the local thickness of metal deposits obtained electrolytically or by other processes. The method is also valid for measuring the thickness of oxide layers obtained on light alloy or ferrous material. The minimum appreciable thickness with this method is 1.5 mm.