Chromized/siliconized diffusion coatings for iron-base alloys by pack cementation

The co-deposition of chrominm and silicon into a 2.25Cr-1.0Mo-0.15C steel, alloy 800, and type 304 stainless steel has been achieved using the pack cementation process. The ferritic coating produced on the 2.25Cr-1.0Mo steel was approximately 225 μm (9 mils) thick, whereas the inward diffusion of chromium and silicon produced a two-phase structure of ferrite and austenite for type 304. Chromium and silicon were incorporated into the anstenitic solid solution upon diffusion into alloy 800