Hot Dip Galvanizing vs Electroplating: Smart Test Method

Summary for hot dip galvanizing vs electroplating Discussion

hot dip galvanizing vs electroplating is usually distinguished by coating thickness and appearance rather than a special standard test. Dr. R.V. Raghavendra asked whether there is a standard method to confirm which zinc coating is present. Dr. Thomas H. Cook replied that hot dip galvanizing after fabrication is virtually always thicker than 2 mils (about 51 microns), while electroplated zinc is usually only a few tenths of a mil, so a simple magnetic thickness gauge can normally tell them apart. Salah Salman added that electroplating is typically brighter and smoother, while hot dip coatings are less smooth; he also noted that continuous hot dip galvanizing can be thin, around 10-25 microns, so appearance alone is not enough. In a later question, Deepak Gupta asked whether 51 microns versus 85 microns affects strength, and the reply explained that galvanizing does not increase steel strength; it is for corrosion protection, and service life generally rises with coating thickness.