Effect of nitrogen alloying on elastic coefficients of austenitic stainless steels

Several nitrogen alloyed austenitic stainless steels (cast and P/M HIPed) were studied. The nitrogen contents ranged from 0.05 wt-% to 1.20 wt-%. Elastic parameters were determined by sound velocity measurements, which were conducted by pulse echo ultrasonic method in an immersion tank. Also the densities and lattice parameters were measured. Nitrogen in excess of 1.5 at-% increases Young's modulus, as well as the shear modulus. Nitrogen decreases the bulk modulus and Poisson's ratio at room temperature. The decreasing effect of nitrogen on the Neel temperature was also observed.