What operating temperature range would be considered most susceptible to chloride stress corrosion cracking in austenitic stainless steel piping?

What operating temperature range would be considered most susceptible to chloride stress corrosion cracking in austenitic stainless steel piping?

• A. Between 120°F and 400°F
• B. Between -20°F and 0°F
• C. Between 0°F and 50°F
• D. Between 400°F and 700°F

Answer: (A)

Chloride stress corrosion cracking in austenitic stainless steels is driven by the combination of chlorides, tensile stress, and a temperature range where the passive film on the steel is vulnerable to breakdown. In practice, this vulnerability is greatest in a mid-temperature window roughly from 120°F to 400°F. Within this range, chloride ions can break down the protective oxide film at the crack tip, enabling localized anodic dissolution and crack growth under the applied or residual stresses typical in piping. Outside this window, the tendency to crack under chlorides diminishes: at lower temperatures the kinetics are too slow for cracking to propagate readily, and at higher temperatures the corrosion mechanisms and film behavior change, making chloride-induced cracking less favorable or leading to other failure modes. So the range of about 120°F to 400°F is the most susceptible for CLSCC in austenitic piping.

Chloride stress corrosion cracking in austenitic stainless steels is driven by the combination of chlorides, tensile stress, and a temperature range where the passive film on the steel is vulnerable to breakdown. In practice, this vulnerability is greatest in a mid-temperature window roughly from 120°F to 400°F. Within this range, chloride ions can break down the protective oxide film at the crack tip, enabling localized anodic dissolution and crack growth under the applied or residual stresses typical in piping.

Outside this window, the tendency to crack under chlorides diminishes: at lower temperatures the kinetics are too slow for cracking to propagate readily, and at higher temperatures the corrosion mechanisms and film behavior change, making chloride-induced cracking less favorable or leading to other failure modes. So the range of about 120°F to 400°F is the most susceptible for CLSCC in austenitic piping.