Research on salt spray and electrochemical corrosion of FeCo-based bulk amorphous alloys

Abstract:

The corrosion resistance of Fe24 xCo24-xCr15Mo14C15B6Y2 (X=0, 2, 4, 6, 17) bulk amorphous alloy was investigated by electrochemical test methods and neutral salt spray experiment, respectively. The alloy formed wide passivation zone in 1mol/L HCl, its EIS spectra was composed of a single capacitive loop, which showing a good corrosion resistance. Combined with the results of polarization curves and AC impedance analysis, it can be obtained that the corrosion resistance of the alloy increases first and then decreases with the increasing of Co content. It gets the best corrosion resistance when the Co content of 20%. Using spectroscopy (EDS) and atomic force microscopy (AFM) to analyze the salt spray result, it can be known that the corrosion products mainly composed of iron and cobalt oxides and their chlorides. Meanwhile, FeCo-based bulk amorphous alloy corrosion degree was changed with Co content varied, and its salt spray corrosion resistance rule is consistent with electrochemical corrosion resistance rule.

Key words:FeCo-based bulk amorphous alloy, corrosion resistance, electrochemical corrosion, salt spray corrosion