Abstract
In the present paper there are reported the results of measurements of chemical diffusion of Al, Cr, Fe, Ni in steel weldments formed by steel A (CSN 412050) additionally alloyed by Al, and by austenitic steel Cr-Ni N (CSN 417242). The measured values of chemical diffusivity show that D(Cr) ~ D(Fe) ~ D(Ni) and that D(Al) is slightly higher than these values, approximately 2 times in ferritic region and 3.5 times in austenitic region. The choice of A and N steels yields the possibility to judge Al diffusivity in both BCC and FCC steel structures. The knowledge of thermodynamic εⁱ Cⁱ and of diffusion εⁱ Cⁱ interaction parameters makes it possible, together with carbon diffusion coefficients in 17242 steel, to calculate carbon redistribution in steel weldments A/N.

Key words
chemical diffusion, Al, Cr, Fe, Ni, steel weldments, high temperatures

Full text (347 KB)