and 77 K. The role of nitrogen alloying and of the temperature decrease is examined during
low-cycle fatigue (LCF) and fatigue crack propagation. Fatigue resistance is enhanced by
the addition of nitrogen in steel at both test temperatures. The results are discussed on the
basis of micro-structural observations. Planar slip of dislocations is found in the nitrogen-
containing steel and is favored by a decrease in test temperature. To some extent, the …