Stress Corrosion Cracking of C-Mn Steel in Phosphate Solutions

Abstract

Annealed C-Mn steel has been shown to fail by transgranular stress corrosion cracking (SCC) in sodium phosphate solutions over a range of potentials and pH's at room temperature. The observed SCC domain is reasonably accurately predicted from fast and slow sweep rate polarization curves. Moreover, the cracking domain boundaries can be calculated with reasonable precision from the thermodynamic properties of the reactants and products involved in the reactions responsible for the various modes of failure at different potentials and pH's.

Environmental Cracking Susceptibility of AISI 422 Stainless Steel in NH4HCO3/NH4OH Solution at 70°C

“…Assuming that the relevant conditions for the cleaning of turbine blades have been adequately reproduced (temperature, cleaning solution composition, electrochemical potential, state of stress, and applied strain rate), these results environmental susceptibility exists. [3][4][5][6][7][8][9] The fact that severe cracking is not observed in this potential range at this strain rate provides some additional assurance that the cleaning solution is not extremely aggressive in terms of EAC of AISI 422 SS. However, the damage produced at the active-passive transition also indicates that the material is not immune under slightly different electrochemical conditions than those expected during the normal cleaning operation.…”

“…The active-passive range is also observed to be one of the most detrimental potential regions for EAC in similar material/environment combinations. [3][4][5][6][7][8][9] The engineering strain rate chosen for the CERT tests reported here is also likely to maximize degradation of tensile properties if turbine blades would occur if the potential during the cleaning process were to decrease to -0.7 V vs Ag/ AgCl.…”

“…For these systems, environmental cracking is best described by the slipfilm rupture-dissolution mechanism. [3][4][5][6][7][8][9] CERT tests were then conducted at the potentials indicated above at a crosshead displacement rate of 7.24 x 10 -7 in/s, which translates to a engineering strain rate of 1 x 10 -6 s -1 for the specimen geometry used. This was within the range of strain rates that produced the maximum susceptibility to environmental cracking for steels in several studies where the slip- Electrochemical Experiments Figure 1 schematically illustrates the electrochemical cell used for the electrochemical experiments.…”

“…[3][4][5][6][7][8][9] For instance, a critical strain rate of 3 x 10 -6 s -1 was cited for pipeline steels in 33% NaOH at 92°C. 8 …”

Stress corrosion cracking in tinplate destined for legume and pet food packaging

“…In this way, the { Beading refers to the corrugations used to reinforce the walls of tin cans. 1 Fast and slow anodic polarisation curves 6 base steel was obtained, on which the polarisations were carried out. The steel sample was mounted on a plexiglass cell, allowing for measurements to be made over a well defined area (26 .…”