Superlattice phase transformation, occurred in the solute enriched region caused by diffusion induced grainboundary migration (DIGM), was found in two kinds of diffusion couples which consist of: (1) low carbon highst...Superlattice phase transformation, occurred in the solute enriched region caused by diffusion induced grainboundary migration (DIGM), was found in two kinds of diffusion couples which consist of: (1) low carbon highstrength steel with hot dipped zinc coating, and (2) commercial pure iron with galvanized zinc coating after isothermally diffusion annealed at different temperatures (500, 560 and 580℃) with various durations. The product of thetransformation is an ordered phase with Li2 superlattice structure which was identified through the analysis by SEM,TEM and AEM. The ordered phase resulted from transformation occurred in the alloyed areas generated by DIGMand DIR The zinc content in this phase is variable, it approaches the stoichiometric composition Fe3Zn as the diffusion time is sufficiently prolonged. The mechanism of the transformation in connection with the process of DIGMand DIR was discussed. DIGM DIR and DIP (diffusion induced phase transformation) are three interrelatedprocessed originated from grain boundary diffusion.展开更多
文摘Superlattice phase transformation, occurred in the solute enriched region caused by diffusion induced grainboundary migration (DIGM), was found in two kinds of diffusion couples which consist of: (1) low carbon highstrength steel with hot dipped zinc coating, and (2) commercial pure iron with galvanized zinc coating after isothermally diffusion annealed at different temperatures (500, 560 and 580℃) with various durations. The product of thetransformation is an ordered phase with Li2 superlattice structure which was identified through the analysis by SEM,TEM and AEM. The ordered phase resulted from transformation occurred in the alloyed areas generated by DIGMand DIR The zinc content in this phase is variable, it approaches the stoichiometric composition Fe3Zn as the diffusion time is sufficiently prolonged. The mechanism of the transformation in connection with the process of DIGMand DIR was discussed. DIGM DIR and DIP (diffusion induced phase transformation) are three interrelatedprocessed originated from grain boundary diffusion.
