Solutions of Different Corrosivity at Cathodic Polarisation

Keywords

stress-corrosion cracking, polarization, hydrogen, protective

Abstract

Stress-corrosion cracking (SCC) pecularaties of X70 steel for main pipelines in solutions with pH from 5,6 to 9,6 at cathodic polarization using slow strain rate tests, volumetry, masometry, optical metallography, and SEM were carried out. Results indicated that maintaining of protective potential for anticorrosion protection of pipelines at the level -1.050 V (that is the maximum protective potential) is not as dangerous as it can be, because can led to SCC by hydrogen embrittlement mechanism. So, decision for choice of maximum protective potential have to accepted depending on corrosivity of environment.

References

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