Evaluation of the active mechanism for acidic SCC induced mechanical degradation: A methodological approach

Effect of Film-Forming Amines on the Acidic Stress-Corrosion Cracking Resistance of Steam Turbine Steel

“…In situ tensile tests were performed at a strain rate of 10 −6 s −1 , by making use of an Instron 5800 tensile testing machine equipped with a 100 kN load cell and a tensile testing cell developed to provide the desired acidic aqueous environment [67]. Details on the in situ CERT set-up as well as on the method development can be found in previous work [68,69].…”

“…Metals 2020, 10, x FOR PEER REVIEW 6 of 21 provide the desired acidic aqueous environment [67]. Details on the in situ CERT set-up as well as on the method development can be found in previous work [68,69]. Tensile specimen geometry (mm) (thickness = 1.5 mm, TD = transverse direction, LD = loading direction) [61].…”

“…Multiple potentiodynamic measurements were performed until a maximum standard deviation of 10 mV for the corrosion potential E corr (V vs. SHE) was obtained. Corrosion rates CR (µm/year) were determined according to the method described in previous work [69].…”

“…Metals 2020, 10, x FOR PEER REVIEW 9 of 21 cracking [68,80]. Since these cracks are only present when having a combination of high local stresses and a corrosive environment, these cracks are presumably the result of SCC [61,68,69]. When examining the fracture surface of the non-coated NiCrMoV steel tested in acidic aqueous environment by SEM, both ductile regions and more brittle zones were observed, as shown in Figure 8 [61].…”

“…This indicates that these cracks were formed because of strain localisation around the main crack at ultimate tensile strength (UTS) and not due to subcritical cracking [68,80]. Since these cracks are only present when having a combination of high local stresses and a corrosive environment, these cracks are presumably the result of SCC [61,68,69].…”