INTERFACE REACTIONS BETWEEN MANGANESE ZINC FERRITE SINGLE-CRYSTALS AND SIO2-PBO-ZNO TERNARY-SYSTEMS

Interface reactions between Mn-Zn ferrite single crystals and SiO2-PbO -ZnO ternary systems were investigated using scanning electron microsc ope, electron probe microanalyzer, and x-ray diffractometer. The addit ion of ZnO in a SiO2-PbO glass resulted in inhibition of formation of the intermediate phase and suppression of dissolution of the ferrite. The interface morphology became a dendrite structure with increase of ZnO concentration in the glass. Appearance of the anomalous concentrat ion profile of Zn and Mn at the ferrite adjacent to the interface was investigated in terms of the dissolved quantity of Mn and Zn ion. It w as found that Zn ion has dissolved from the ferrite into the glass mel t during the reaction and Mn ion in the ferrite dissolved into the gla ss melt more than Zn ion, resulting in changing the undissolved ferrit e adjacent to the interface into a Zn-rich Mn-Zn ferrite, Mn0.16Zn0.85 Fe2O4, after reaction with 57SiO(2)-38PbO-5ZnO (in mol %) glass. It wa s considered that the source of the hump of Zn concentration at the fe rrite adjacent to the interface would be the undissolved, remaining Zn ions. A microscopic model was suggested. (C) 1995 American Institute of Physics.