S. Alhassan et al., EFFECT OF MICROSTRUCTURE ON CORROSION OF STEELS IN AQUEOUS-SOLUTIONS CONTAINING CARBON-DIOXIDE, Corrosion, 54(6), 1998, pp. 480-491
Citations number
29
Categorie Soggetti
Material Science","Metallurgy & Metallurigical Engineering
The influence of microstructure on the corrosion rate of steels in a c
arbon dioxide (CO2)-containing aqueous solution was measured experimen
tally as a function of pH, temperature, and partial pressure of CO2. A
n attempt was made to quantify and relate the microstructure to the co
rrosion rate. The effect of alloy microstructure was Increasingly evid
ent at temperatures up to 60 degrees C but diminished above 60 degrees
C. The corrosion rate increased with temperature In the activation-co
ntrolled regime, where a nonprotective iron carbonate (FeCO3) scale fo
rmed. Diffusion-controlled corrosion through a stable scale of iron hy
droxycarbonate (Fe-2[OH](2)CO3) was responsible for lowering the corro
sion rate above 60 degrees C. Under a diffusion-controlled corrosion m
echanism microstructure of the steel had no effect on corrosion rate.