Q. I am the engineering manager at my plant and would like to reduce our manufacturing costs by changing our transformer material from galvanneal to pickled hot-rolled steel. Do you have any data comparing corrosion performance between these two materials? Both items will be post-painted with a powder coating. A.N.
A. The corrosion resistance of galvanneal-treated steel is considered far superior to pickled hot-rolled steel, but I have no data in my archives to support this. This kind of information usually is generated by manufacturers, metal pretreatment suppliers and steel mills, so I suggest you contact your pretreatment supplier. Remember that the hot-rolled steel also will have to be pretreated before powder coating. Although it won’t provide the same level of corrosion protection as galvanneal, I would recommend a zinc phosphate pretreatment.