On the determination of low nitrogen concentration gradients in austenitic CrNi(Mo) steels

For the determination of diffusion coefficients by using the model “diffusion into a plate” methodical examinations were carried out on samples of austenitic steel that had been nitrided in their marginal zones for 1.5 h at 1523 K. For recording of the concentration of N as a function of the distance from the surface electron-probe microanalysis (EPMA) and the precision determination of the lattice parameters by Kossel technique were applied. Both methods yield comparable results.