The corrosion behaviors of Fe-based bulk metallic glasses in a sulfuric solution at 70 °C

The corrosion behaviors are investigated for Fe-based bulk metallic glasses of Fe71.4−xC7.1Si4.4B6.5P8.6CrxAl2.0 at% (x = 0, 2.3∼12.3) in 9.7 M H2SO4 at 343 K. The electrochemical analysis results indicate that the corrosion rate decreases with the increase of chromium content. A significant decrease in the corrosion rate occurs as the Cr content increases from 6.3 at% to 8.3 at%. The amorphous alloy with 12.3 at% Cr exhibits a remarkably lower corrosion rate than that of AISI 316L. The corrosion rate variation with the Cr content is discussed based upon the results of electrochemical, microstructural and chemical analysis for the corrosion product layer. The excellent corrosion resistance of the amorphous alloy with 8.3 at% Cr (9.5 wt%) are demonstrated compared with the conventional stainless steels with high Cr contents (13∼18 wt%).