Solute segregation to grain boundaries and free surfaces in an FeSi multicomponent alloy

Influence of phosphorus enrichment at grain boundaries on energy of intergranular fracture in Fe–Si–P alloys

“…It is known that silicon promotes the segregation of phosphorus at the grain boundaries of -iron by raising its activity in solid solution 14 and that there exists the negative correlation between the grain boundary concentrations of phosphorus and silicon. 13 In this work, all these suggestions were confirmed experimentally (Fig. 1).…”

“…The values of X S Si registered for the alloy C (0.9 š 0.1 at.%) that are lower in comparison with the crystal volume (4.8 at.%) reflect this depletion exemplary. A similar behaviour of silicon was observed by Lejček and co-workers 13 for Fe-6 at.% Si-P-S alloy at 600°C.…”

Solute segregation at grain boundaries

“…This type of the behavior was observed in an Fe-Si base alloy. As described in Section 2.3, an enrichment of carbon and phosphorgs and a depletion of silicon characterize the segregation behavior at the {013} symmetrical tilt grain boundary at 873 K while nitrogen is practically not detected there [44,88]. Annealing of the sputtered fracture surface from this boundary, i.e., now a (013) free surface, at the same temperature, however, leads to formation of stable SixNy 2-D surface compounds at this surface thus preventing segregation of other elements.…”

“…Annealing of the sputtered fracture surface from this boundary, i.e., now a (013) free surface, at the same temperature, however, leads to formation of stable SixNy 2-D surface compounds at this surface thus preventing segregation of other elements. In denitridized and decarburized samples, on the other hand, enrichment of phosphorus and depletion of silicon were found again at the grain boundary whereas pronounced sulfur segregation dominates at the free surface and is accompanied by a weaker phosphorus and silicon segregation [88,89]. Model calculation of the segregation behavior in an Fe-Si (P, S) alloy demonstrated that the differences in the behavior of both crystallographic interfaces are controlled by the free energy of segregation of individual components.…”

“…9). From the phenomenological point of view these qualitative differences may be considered as a generalized anisotropy ofinterfacial segregation [88,89].…”