Aluminizing and chromizing bed treatment by CVD in a fluidized bed reactoron austenitic stainless steels

The deposition of Al and Cr on steel coupons by chemical vapor deposition i n fluidized bed reactors (CVD-FBR) has been studied. Before performing the experiments, thermochemical calculations were run using the free-energy min imization method afforded by the HSC Chemistry software. Metal sub-halide c hemistry was used to produce the gas precursors of deposition. With this me thod we have achieved 10 mu m thick Al coatings at low deposition temperatu res and short deposition times. However, we have not yet succeeded in the d eposition of Cr and further work is needed. (C) 1999 Elsevier Science S.A. All rights reserved.