Functionally Graded Coating for Steels by Reaction Diffusion Using FeAl_3 Powder
The powder liquid coating method has successfully been applied to a commercially available pure iron and a carbon steel (JIS-S45C) using FeAl<sub>3</sub> powder. The coated layer is found well graded in terms of microstructure, chemical compositions and hardness, so that the coated layer is much stronger for thermal shock than that made by a conventional aluminizing method. Changes in the graded microstructure during coating procedures are studied; it is noted that an FeAl/FeAl<sub>2</sub> eutectoid structure formed in the coated layer shows 927HV and relatively high toughness. Although the present coating technique needs to heat a sample up to an elevated temperature as high as 1473 K, the prior austenite grain size of the carbon steel was refined by so-called Grange method, without accompanying any serious damages in the coated layer.
- ISIJ international
ISIJ international 40(10), 1029-1034, 2000-10-15
The Iron and Steel Institute of Japan