Nitrogen containing alloys were evaluated concerning their resistance against pitting and stress corrosion cracking under hot water conditions up to 523 K. It was shown that nitrogen containing CrNiMo alloys are more resistant to localised corrosion up to 523 K than nitrogen flee steels and CrMn steels with high nitrogen contents. The resistance against localised corrosion is strongly reduced with increasing temperature. The repassivation behaviour of the nitrogen containing steels is also better than for the nitrogen flee steels but decreases with temperature. Beside two alloys with significant high repassivation potentials at high temperatures all others show pitting induced Stress corrosion cracking at temperatures above 473 K. The results are discussed concerning the stability of passive layer, which is influenced by the chemical composition rather than by the nitrogen content. It was established that stress corrosion cracking and hydrogen embrittlement of nitrogen containing alloys are controlled by the same mechanism. Both damaging processes occure if the empirical pitting resistant equivalent number (PREN) is low as well as the stacking fault energy and hydrogen diffusivity and the hydrogen solubility is high.
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