Precipitation of nitrides in iron-based binary and ternary alloys; influence of defects and transformation-misfit stresses
نویسنده
چکیده
The effect of the initial microstructure (recrystallized or cold-rolled) on the nitride-precipitation process upon gaseous nitriding of ternary, ferritic, Fe-Cr-Al alloy was investigated at 450°C. In the recrystallized specimens, precipitation of metastable ternary, cubic, NaCl-type mixed Cr1xAlxN took place, whereas in the cold-rolled specimens precipitation of firstly binary cubic NaCltype CrN and secondly binary cubic NaCl-type AlN occurs. The difference in nitriding response for the different initial microstructures could be ascribed to the potential preference for nucleation of CrN precipitates on dislocations.
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