Effect of alloyed Cr on corrosion behavior of low‐alloy steel in wet atmosphere

Abstract

The effect of 1.5% Cr on the corrosion resistance of low-alloy steel in a simulated mine environment was studied. To clarify the effect of Cr on the corrosion of low-alloy steel in the wet environment at the initial stage of corrosion, salt spray corrosion tests were performed to simulate the corrosion process in the field, and the bare steel and corrosion products were characterized. The results showed that the addition of 1.5% Cr reduced the surface potential and the kinetic tendency of the corrosion reaction, making the corrosion rate at the initial stage of the test lower than anticipated. An increase in Cr content significantly elevates the level of α-FeOOH. The corrosion product film (CPF) had a bilayer structure, with α-FeOOH of Cr-rich and Cr(OH) 3 were found in the inner layer and at the junction of the inner and outer layer. The CPF had a dense structure that effectively reduced electrochemical reaction activity and improved corrosion resistance.

Influence of UV Illumination on the Corrosion Behavior of New 3Ni Weathering Steel in Marine Atmospheric Environments

“…Cl is mainly enriched in the defects of the rust layer, such as holes and microscopic cracks, and the holes that destroy the denseness of the rust layer gradually shift from the outer to the inner rust layer. Corrosion-resistant alloy elements such as Cu, Ni and Mo are enriched in the inner rust layer during the formation of the rust layer, resisting the erosion of Cl ions and promoting the formation of a dense rust layer [34,35].…”

The Influence of 1 wt.% Cr on the Corrosion Resistance of Low-Alloy Steel in Marine Environments

“…Cr [9][10][11][12][13], as a universally recognized primary corrosion-resistant element, has been the subject of extensive research. Studies have shown that Cr can shift the self-corrosion potential of the steel matrix positively, and when the Cr content is higher, a passive film can form.…”

Corrosion Behavior of 3Cr Steel in Simulated Oilfield CO₂ Environment

“…The gas injection flooding process can make the downhole string facing a certain content risk of CO2 corrosion. Especially at the extraction process, the concentration of CO2 is even higher, when mixed with the formation water which has a high degree of mineralization(19-22×10 4 mg/L) and high content of chloridion (>8×10 4 mg/L), a serve corrosion risk would take to the downhole tubing and casing [8].…”