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The stacking fault energy (SFE) in a set of experimental Ni–Cr–Fe alloys was determined using line profile analysis on synchrotron X-ray diffraction measurements. The methodology used here is supported by the Warren–Averbach calculations and the relationships among the stacking fault probability ( α ) and the mean-square microstrain ( e 2 L >). These parameters were obtained experimentally from cold-worked and annealed specimens extracted from the set of studied Ni-alloys. The obtained results show that the SFE in these alloys is strongly influenced by the kind and quantity of addition elements. Different effects due to the action of carbide-forming elements and the solid solution hardening elements on the SFE are discussed here. The simultaneous addition of Nb, Hf, and, Mo, in the studied Ni–Cr–Fe alloys have generated the stronger decreasing of the SFE. The relationships between SFE and the contributions on electronic structure from each element of additions were established.

An electron back scattering diffraction characterization analysis of a high temperature gas nitrided UNS S31803 duplex stainless steel was performed. Nitriding treatments were carried out between 1423 and 1473 K, for times varying between 0.18 and 86.4 ks, under nitrogen partial pressures varying between 0.03 and 0.15 MPa. Upon investigation, these samples displayed a fully austenitic surface layer on a ferritic–austenitic duplex core. The grain boundary character distribution of surface austenitic layers strongly varied as the nitriding parameters were varied; low- Σ CSL grain boundary fractions between 0.35 and 0.65 were obtained. Conversely, the microtexture mainly depended on nitriding time, being only slightly affected by nitrogen partial pressure or temperature changes. At the earliest stages of nitriding, austenitic cases displayed an intense microtexture with two major texture components, {0 0 1}〈1 0 0〉 and {0 1 1}〈2 1 1〉, which weakened as nitriding time was increased.