Abstract
In hot dip galvanizing reaction, as previously reported, iron-zinc intermediate phase layers are formed successively in the order of the ζ, palisade δ1, Γ, Γ1 and compact δ1 phases, and their growth does not follow the parabolic law. In order to speculate rate controlling process in the galvanizing reaction, in this paper, growth curves of the intermediate phase layers formed by galvanizing reaction at 460°C are calculated numerically using Wagner's diffusion equation on the moving velocity of phase boundary.
The results obtained are as follows:
(1) The calculated growth curves fit well with those obtained experimentally in a previous study.
(2) The characteristic growth kinetics of palisade δ1 layer, decrease in growth rate accompanied by formation of compact δ1 layer and twice rapid growth after appearances of Γ phase layer and of compact δ1 layer, could be explained by use of Wagner's equation.
(3) The growth rate of the intermediate phase layers in galvanizing reaction seems to be controlled by diffusion process.
