화학공학소재연구정보센터
Journal of the Electrochemical Society, Vol.165, No.9, C515-C523, 2018
Computational Evaluation of the Influence of Various Uniaxial Load Levels on Pit Growth of Stainless Steel under Mechanoelectrochemical Interactions
Numerical modelling of the effects of different applied load levels on the growth of metastable single pit in stainless steel is the subject of the present work. A cellular automata model integrated with finite element analysis is used, taking into account both the electrochemical reactions during metastable pitting growth process and the real-time influence of local stress/strain distribution at pit surface on anodic dissolution. Specifically, in the current work the impacts of uniaxial load levels on pitting corrosion for various conditions of passive layer degradation extents and hydrogen ions diffusion coefficients are quantitatively assessed in terms of current transient. For a general condition with uniaxial applied load level increases from 0 MPa to 250 MPa, the ascending trend of current transient and current density transient is observed due to the increase of plastic strain accumulation at pit bottom, revealing the enhancement of metastable pit growth rate. Meanwhile, the critical magnitude of load level enabling metastable pitting to alter into the development of stable pit for each condition is discussed and predicted. (C) 2018 The Electrochemical Society.