Interface Morphology Between the Aluminide Layer and Iron Substrate in the Hot-Dip Aluminizing Process

Abstract

AbstractThe morphology of the interface developed in the hot-dip aluminizing process between the aluminide layer and the iron substrate was investigated by metallography.A serrated interface was generally found between the aluminide layer and the iron substrate. However, a planar interface was produced by the addition of carbon and silicon in the iron substrate or the addition of silicon in the aluminum bath. This interesting phenomenon is explained on the basis of the nucleation of each aluminide grain at the contact interface. The serrated interface is believed to result from preferential nucleation of aluminide crystallites on certain crystallographic planes of the iron substrate, whereas the planar interface results from uniform nucleation at all sites. It was also determined that the structure of the iron substrate has no effecton interface morphology, and that the aluminide layer has a preferred orientation of (002). Resume La morphologie de l'interface qui se developpe dans le procede d'aluminage p...