The influence of the sintering regime on the stability of the SmCo5 phase

The purpose of this investigation was to establish the correlation between the sintering conditions (temperature and time) and the stability of the SmCo5 phase, expressed by the intensity of its most important diffraction peak. The sintering and heat treatment was performed under a vacuum of 150 Pa. Sintering was investigated in the temperature interval from 1100 to 1180 degrees C, for sintering times of 30, 45 and 60 min, while the temperature and duration of the heat treatment were kept constant. The content of the SmCo5 phase, as the carrier of the magnetic properties, was observed by X-ray diffraction analysis of the polycrystalline specimens. It was established that there is a dependence of the intensity of the diffraction peak, which corresponds to the (111) plane of the SmCo5 phase, on the sintering time and temperature. A regression model was obtained that showed the intensity of the diffraction peak to be dependent upon squares of both the sintering time and temperature. (C) 1997 Elsevier Science B.V.