PRELIMINARY-OBSERVATIONS OF THE THERMODYNAMIC PREDICTIONS OF FE-CR-NI ALLOYS IN COAL GASIFIER ENVIRONMENTS

The construction of thermodynamic stability diagrams for the Fe-Cr-Ni systems is discussed. The constructed diagrams are used to predict materials behavior at coal gasifier oxygen and sulfur potentials. Some preliminary experiments are run to compare predicted results with experimental observations. Powder mixtures of FeS, NiS, and Cr2O3are used to observe the formation of the iron-chromia and nickel-chromia spinels at 871° C. Only the iron-chromia spinel was observed. No spinels were observed on 310 stainless steel samples exposed to the same environment. © 1979 Plenum Publishing Corporation.