Using X-ray analysis for the optimization of the sintering of SmCo5 magnets

Keeping in mind the importance of the sintering and heat treatment conditions for the achievement of optimal magnetic structures, another approach was utilized to determine the most convenient technological parameters of sintering under the given heat treatment conditions. The purpose of this investigation was to establish the correlation between the sintering conditions (temperature and time) and the content of the carrier of magnetic properties, expressed by the intensity of its diffraction peak corresponding to the (111) plane. Sintering was investigated in the temperature interval from 1100 to 1180 C, for different sintering times. The heat treatment, for all the investigated sintering conditions, was performed in the interval from 900-920 C for 90 minutes. Vacuum was used as the protection atmosphere during the sintering and heat treatments. The content of the SmCo5 phase was observed by X-ray diffraction analysis as a function of the regime of sintering and heat treatment. From the obtained diffractograms, the intensity of the diffraction peak, corresponding to the (111) plane of the SmCo5 phase was compared for the investigated sintering and heat treatment regimes. By mathematical modelling, it was established that there was a correlation between the intensity of the diffraction peak, corresponding to the (111) plane of the SmCo5 phase, and the sintering time and temperature for constant heat treatment conditions. The obtained mathematical models show that there is a complex dependence between the intensity of the diffraction peak and the sintering time and temperature for defined heat treatment conditions. Considering that this dependence has a maximum, the optimal sintering conditions were simultaneously established by calculating the values of the sintering time and temperature for which the given dependence has its maximum