Abstract
Gold was electrodeposited from KCN bath on spheroidized 0.88% carbon steel. The nucleation of cementite region occurred later than that of ferrite region, and the number of nuclei formed on the former was smaller than that on the latter. However, the lag-time for the nucleation of cementite was shortened and the number of nuclei of these regions increased by the electrodeposition under a high current density. The nuclei of the both regions grew up independently with each other; they formed an insular and net-work structures, and finally, made up continuous films. The electron diffraction pattern of Au plate crystals electrodeposited on ferrite under a low current density gave rise to an N-pattern and a weak Debye-Scherrer ring; while, that of Au plate crystals on cementite consisted of only a Debye-Scherrer ring. The electrodeposition under a high current density was effective for improvement in Au film's epitaxy, and the Au plate crystals formed on ferrite made up good single crystals; while those formed on cementite had a tendency to be arranged in one orientation.
