MAGNETOTHERMAL INVESTIGATION OF THE KINETICS OF DEFECT REACTION IN THE COGA INTERMETALLIC COMPOUND

The kinetics of the formation and of the annealing out of Co antistruc ture atoms in the CoGa intermetallic compound have been investigated b y magnetothermal analysis. The annealing out was found to be influence d by a single defect type. A quantitative analysis of the susceptibili ty vs. temperature curve of quenched Co50Ga50 sample yielded the fract ion of antistructure atoms. The triple defect model was used to calcul ate the amount of vacancies. The migration enthalpy H-m was determined for the quenching temperatures 1000 degrees C, 900 degrees C, and 850 degrees C and found to be 1.78+/-0.12 eV, 2.16+/-0.12 eV, and 1.8+/-0 .2 eV respectively. The triple defect type, the amount of vacancies an d the migration enthalpy for 1000 degrees C are in agreement with data reported in the literature.