Effect of Hydrogen Sulfide and Chloride on the Passive Film Structures of Stainless Steel Type 316L

Fatigue corrosion behavior of friction‐welded stainless and carbon steel dissimilar joint

“…The creation of these anodic sites is mainly due to the presence of exposed and non‐passivated areas, where the metal becomes locally active. The presence of chlorine ions hinders the re‐passivation of the metals, thus favoring the pitting mechanisms 34 . The geometrical features of this corrosion mechanism have a detrimental effect on the fatigue resistance of welded joints, as swells can act as nucleation sites for cracks 44,45 …”

“…Cracking and failure due to the combined presence of mechanical loads and an aggressive environment are addressed as “environmental‐assisted cracking (EAC),” and it is usually distinguished into three different damaging processes: corrosion fatigue, stress corrosion cracking (SSC), and ad hydrogen embrittlement 3,33 . Corrosion fatigue is the result of the combined action of a cyclic load in the presence of a corrosive environment 34 : The fatigue process is believed to cause the rupture of protective oxide films upon which corrosion is accelerated, but many other corrosive phenomena are known to occur during the fatigue loading of the components. Stress corrosion cracking is defined as the mechanical–chemical process that causes cracking of a component subjected to external static or quasi static and/or residual tensile stresses at lower stress values than the tensile strength of the material itself 35,36 .…”

“…The presence of chlorine ions hinders the re-passivation of the metals, thus favoring the pitting mechanisms. 34 The geometrical features of this corrosion mechanism have a detrimental effect on the fatigue resistance of welded joints, as swells can act as nucleation sites for cracks. 44,45 While the role played by galvanic corrosion in the initiation of fatigue damage in the presence of dissimilar material couplings is recognized in the literature, little has been published regarding the possibility of controlling the corrosive process by cathodic protection with the aim of mitigating the synergistic effect between the corrosive process and cyclic mechanical stress in the initiation stages and the propagation of damage.…”