Figure gives the approximate time for austenitic stainless steels, grade A2 (18/8 steels), with different carbon contents in the temperature zone between 550 °C and 925 °C before risk of intergranular corrosion occours.
The following stainless steel grades are recommended if there is a risk of intercrystalline corrosion:
- A3 or A5 stabilized
- A2 or A4 with max. carbon content 0,030 % (marked with «L»)
With lower carbon contents, the resistance against intergranular corrosion is improved.