Der Einfluß von Stickstoff auf die korrosionschemischen Eigenschaften lösungsgeglühter und angelassener austenitischer 18/10 Chrom-Nickel- und 18/10 Chrom-Nickel-Molybdän-Stähle. - I. Ausscheidungsverhalten der Stähle

Influence of nitrogen on the corrosion behaviour of solution treated and annealed austenitic 18/10 chromium-nickel and 18/12 chromium-nickel-molybdenum steels. - I. Precipitation behaviour of the steels Investigations into the corrosion behaviour of CrNi steels with (weight-%) 0.019–0.029 C, 18.5 Cr, 11 Ni, 0.022–0.138 N and 0.020 to 0.031 Cr, 17.2 Cr, 13 Ni, 2.6 Mo, 0.028 to 0.130 N by the Strauß-Test, the Strauß-Test under rigid condition and the Huey-Test. The first part of this paper is devoted in particular to the analysis of structural constituents and in particular to precipitations. In the molybdenum-free steel heat treatment results in precipitation of M₂₃C₆ and Cr₂N, the precipitation of the first being independent from nitrogen content. In case of the molybdenum-bearing steels the precipitation of M₂₃C₆ is independent from nitrogen content too but is shifted toward higher temperatures. The precipitation of Cr₂N is slowed down by Mo. The precipitation of other phases (chi-, sigma- and Z-phases) is affected differently by nitrogen.