A new technology of composition treatment of steel heat treat-ment in molten salt and its surface aluminum-electroplating

The electroplating aluminum layer on Q235 steel surface in NaClKCl molten salt had been obtained when the steel was heattreated. In this paper, the technical parameters of electroplating in molten salt and corrosion resistance as well as oxidation resistance of electroplating layer had been studied primarily. It shows that the structure of coating was singlephase aluminum; the thickness of plating was determined by the technical parameters of electroplating. The thickness of plating increased with the increase of current density and electroplating time. After electroplating aluminum on Q235 steel, the corrosion resistance and high temperature oxidation resistance of plating layer have been improved dramatically. After electroplating aluminum in molten salt, the steel can be taken out from molten salt directly to quench. Consequently, besides all capability of heat treatment is obtained, the surface of steel features very good corrosion resistance.