Metallic materials used in certain areas of the chemical process industry face high
temperature attack in the form of oxidation, sulfidation, carburization, halogen attack, etc. One
approach to defending metallic materials against high temperature corrosive attack is through the use of
protective coatings. Although several coating methods are available, halide-activated pack cementation
is a coating process of choice due to its versatility and cost-effectiveness. Traditionally pack
cementation has been utilized to apply aluminum, chromium or silicon-rich coatings. The coating
process is reviewed and a model to predict the kinetics is outlined. The effective utilization of this
process to achieve desired results is discussed.
Keywords: coatings, pack cementation, halide-activated, aluminizing, chromizing, siliconizing