|MadSci Network: Engineering|
I will make an assumption that you are trying to detect the presence of galvanized plating on cold rolled steel during the rolling process ("on the run"). One consideration is a resistivity test. Zinc used in the galvanizing process is approximately half the resistivity value of carbon steel. However, the quality of any detection method is directly related to the surface cleanliness of the steel. You may want to try steel wool wipers used as a cleaning agent. Another method is exposing the steel to the outside environment until the cold rolled steel starts to oxidize. The galvanized sections will not. I hope the may give you some ideas. Reference: http://www.ai.mit.edu "Electrical Resistivity of Materials"
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