Avaliação da permeação do hidrogênio através da liga Zn-Ni eletrodepositada sobre o aço SAE 1020.

Abstract

The embrittlement by hydrogen, of a metal or an alloy, is an industrial problem that can lead to structural damage, when in optimal conditions it will happen. Based on this premise, the present study aimed to study the mitigating effect of hydrogen permeation, by the Zn-Ni alloy electrodeposited on SAE 1020 Steel. This alloy, with low carbon content, is one of the most commonly used steels in the process industry , with an excellent cost-benefit ratio compared to other steels intended for the same purpose. Two methodologies were chosen to galvanize this steel with the Zn-Ni alloy; one based on chlorides and the other based on sulfates, in order to compare their effects to hydrogen permeation. Initially, a characterization of the electrochemical corrosion of these and its morphological analysis was performed, where it was found that these coatings protect the base metal both to corrosion and hydrogen diffusion, but the Zn-Ni electrodeposition process based on sulfates obtained a higher nickel concentration and better corrosion resistance according to the obtained data and permeation. Zn-Ni coatings decreased the susceptibility of SAE 1020 to hydrogen permeation; where the coating based on sulfates obtained an elongation ratio of 95%.