On Erosion of Steel Plates in a Molten Zinc Bath

Abstract

The erosion of mild steel has been studied by E. J. Daniels in detail, but it was not understandable what composition steel should be used. There is an opinion that one should use a deoxidized and high-tensile strength steel plates such as boiler plates for zinc dipplating kettles. However, concerning the erosion by molten zinc bath, it is not always good to use such kinds of steel plates. It happens sometimes that a good erosion resistance to molten zinc bath is proved when an old steel plate is used which has been made by an inexperienced steelmaking technique. These are influenced by many factors. In this experiment, the author investigated the influences of carbon, manganese, silicon contents in steel plates, the deoxidation of steel, the molten zinc bath temperature and effects of aluminum addition in the zinc bath.
Experimental results show that a low-carbon steel plate shows a good erosion resistance molten zinc, and about 0·1%C steel is good for the practical use, and a deoxidized steel shows good erosion resistance to molten zinc bath. On the contrary, a high-silicon or a highmanganese steel shows bad results, while aluminum-deoxized steel shows a good erosion resistance.
Molten zinc bath is erosive to iron at near 500°C, for there is a peritectic reaction in the Fe-Zn diagram. It is desireable to operate dig-plating at a low temperature of 450°C for the long use of the dip-plating kettle.
The erosion of steel plates in molten zinc is decreased by about 1/2 at the same temperature in the case of the 0·2% aluminum addition in molten zinc as comparted with a simple zinc bath.
Stainless steels shows a good erosion resitance but it can not be used from the economical point of view.