In conventional nitriding i.e. above 500 C, there is a high possibility of formation of chromium nitride at the GB (also known as sensitization) which causes the decrease in the corrosion resistance because the amount of Cr is now decreas near the GB region. But the plasma nitriding treatment mostly carried out at lower temperatures (less than 500) so no sensitization, people even reported a increase in corrosion resistance.
From my experience, nitriding (whether normal gas nitriding or plasma nitriding) worsens the corrosion resistance of all stainless steels. Stainless steels are corrosion resistant due to form a thin Cr2O3 layer on the surface (passivation) but nitriding prevents this process.
Yes it can adversely affect the corrosion resistance significantly. In fact any treatment of austenitic ss involving thermal effect is prone to deteriorate its corrosion resistance if it is not done carefully with necessary control. The control is most important.
- Badges
- Science topic
- Similar topics
- Entomology
- Resistance