Estudo da correlação entre corrosão sob tensão e permeação de hidrogênio em aço carbono utilizando técnicas eletroquímicas para verificação da influência do meio H2S no aço utilizado

Abstract

Steels used in pipelines operating in sour service environment are subjected to high pressures and high concentrations of H2S, and this environment is favorable for the occurrence of corrosion of the material. Several types of damage can occur in this environment, and the stress corrosion cracking and the hydrogen embrittlement are object of this research, as well as generate early cracks making the material vulnerable and reducing its lifetime. The objective of this study was to correlate the influence of hydrogen embrittlement and of stress corrosion cracking. Permeation tests were performed to obtain the hydrogen diffusion coefficient and stress corrosion tests were done to obtain the susceptibility of the material to such corrosion. It is known that the chemical composition and the microstructure of the material influence the characteristics of these processes, thus micro-purity tests and metallographic analysis were performed. The susceptibility of low alloy steels to stress corrosion cracking and hydrogen embrittlement was evaluated.