INTERACTION OF Ce AGAINST Cu,P OR Ti IN Fe-BASE SOLUTION

The equilibrium product in Fe-Cu-Ce,Fe-P-Ce or Fe-Ti-Ce solution have ben Mentifiedto be Ce_2O_2S,but not the intermetallic compounds of Ce against Cu,P or Ti.The equilibriumeonstant of Ce_2O_2S=2Ce]+2O]+S] and the interaction coefficients between solutes inFe-base solution have been determined as follows:K_(Ce_2O_2S)=2.57×10~(-5)e_(Ce)~(Cu)=-0.49;e_(Ce)~P=1.77;e_(Ce)~(Ti)=-3.62e_(Cu)~(Ce)=-0.22;e_P~(Ce)=0.39;e_(Ti)~(Ce)=-1.23ε_(Ce)~(Cu)=-128.0;ε_(Ce)~P=-224.1;ε_(Ce)~(Ti)=-710.0Ce decreases the activities of Cu and Ti in Fe-base solution and increases their solubifities,aswell as increases the activity of P and decreases its solubility.