Research on the Influence of Mo on the Corrosion Mechanism of 1%Ni Weathering Steel in Simulated Marine Atmospheric Environments

This study focuses on researching the influence of Mo on the corrosion mechanism of 1%Ni weathering steel (WS) in simulated marine atmospheric conditions. The Mo element is involved in the reaction, and after hydrolysis, MoO2 and MoO3 are produced. The deposition of MoO2 and MoO3 occurs in cracks and fissures, rendering the rust layer more uniform and homogeneous. It also furnishes nucleation sites for amorphous oxyhydroxide, which in turn promotes the interweaving of a nanosized oxyhydroxide network. As a result, the rust layer develops into a physical barrier that acquires a protective capacity. Only some of the Mo ions migrate to the vicinity of the Ni element for the hydrolysis reaction, which leads to the difficulty in improving the corrosion rate of the steel with a high Mo content. Hence, the content of Mo element can be controlled within 0.3–0.5% for the 1Ni WS.