Abstract
By using mixed powder compacts of Sm-60.5wt%Co and Sm-62.5wt%Co, the reaction process which occurred between SmCo5 and 60wt%Sm-40wt%Co powders during liquid phase sintering was investigated mainly by means of EPMA and X-ray diffraction method.
The results obtained were as follows: The liquid produced by the peritectic reaction at 1075°C upon heating process, played an important role for the liquid phase sintering of the SmCo5 permanent magnet, and it was confirmed that this liquid penetrated to make a network along the grain boundaries and had the effect of restraining the grain growth. The considerably strong X-ray diffraction peak of Sm2Co7 phase observed in the Sm-60.5wt%Co specimen became weaker with increasing Sm content, and extremely weak peak of Sm2Co7 was recognized in the Sm-62.5wt%Co specimen. On the other hand, in the specimen containing higher amount of Sm than Sm-62.5wt%Co, the peak of Sm2Co17 was observed.
