鉄鋼の溶融亜鉛めつきにおける金属間化合物相の成長

抄録

The previous experimental results on the formation and growth kinetics of intermediate phases in reaction between solid iron and solid or liquid zinc at various temperatures have been investigated in more details. In a function of temperature T(K) and time t(min) A(T, t) = T (logt +16.7), beginning times of characteristic formation and growth processes of the intermediate phases are constant irrespective of reaction temperature and whether zinc is solid or liquid. Irrespective of temperature and zinc state, phase growth curves using A (T, t) instead of t represent the almost similar shapes which change with occurences of the above characteristic processes. The relation W = ktⁿ shown in many previous papers has roughly been obtained in this study, where W is thickness of intermediate phases and t is reaction time in hot dip galvanizing. Difference in values of the exponent n among investigators seems to be due to differences in their experimental temperatures and times. Since the phase growth curves do not correctly obey the relation W = ktⁿ using a single n value, rate determining process in hot dip galvanizing reaction should be discussed from another standpoints.