Electrochemical Mechanism and Preparation of Cr-Low-Carbon Steel Composite in a NaCl-KCl-NaF-Cr_2O_3 Molten Salt

摘要

Fe-Cr Alloy/Low-Carbon Steel Composite was demonstrated in NaCl-KCl-NaF-Cr_2O_3 molten salt system by electrodeposition method successfully. The electrochemical reaction mechanism and the electro-crystallization process of chromium in molten salt system were investigated by cyclic voltammetry theoretically and by XRD practically. It was found that the electrochemical reduction of Cr(III) takes place in two steps, and the electro-crystallization process of Cr is an instantaneous hemispheroid three-dimensional nucleation process. Then the optimum preparation conditions, including current waveform and current density, are obtained. And the corrosion resistance test shows that the corrosion resistance increases with the increase of Cr content.