Surface effects in batch galvanizing of silicon containing steels

Abstract

There is a significant commitment by industry to understand the mechanism of the silicon induced modification of the Fe–Zn coating during batch galvanising. Considerable emphasis has been placed on solving this problem through investigation of substrate surface treatment. This article reviews pertinent literature dealing with surface effects associated with galvanising of silicon containing steels. Relevant observations were grouped together to help to establish the influence of crystallographic orientation, subsurface oxidation, strain energy, and topography on the formation of a reactive coating. This includes a critical discussion of the major factors and their interaction with thermodynamic instabilities informing reactive structure. It was found from the literature that subsurface oxidation and topographical effects had the greatest influence on the silicon reactivity phenomenon. However, these observations do not directly lead to economically viable solutions to the problem.MST/1173