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用金相、X光、高功率衍射、电子探针及热磁分析等手段,对成分为Sm_(0.5)Ce_(0.5) (Co_(0.824)Cu_(0.118)Mn_(0.059))_(6.8)合金铸态、高温烧结及时效前后的磁体进行了相组成的研究。也对氢气,氩气下烧结的磁体进行了比较。试验结果表明:合金铸态存在着CaCu_5型(1:5相)和Th_2Zn_1,(Th_2Ni_(17))型(2:17相)。氩气保护下在1130℃淬火的试样主要是六角型2:17相(缺陷型)。它与低的内禀矫顽力相对应。也存在少量的Sm_2O_3。经750℃,600℃多阶时效淬火的试样,发现在六角型2:17基相中,伴随着调幅结构的出现,析出了少量的菱形2:17相。它与高的内禀矫顽力相对应。氢气保护下,于1130℃淬火的试样,发现其内禀矫顽力也相当高。此时也观察到第二相的析出。第二相以最佳尺寸析出,造成了畴壁钉扎点,从而对内禀矫顽力有较大的贡献。
(0.5) (0.8 0.8) Cu 0.118 Mn 0.059) _ (6.8) were characterized by means of metallography, X-ray diffraction, high power diffraction, electron probe and thermal analysis. The phase compositions of the as-cast, as-sintered and aged magnets were studied. Magnets sintered under hydrogen and argon were also compared. The results show that there are CaCu_5 (1: 5) and Th_2Zn_1 (Th_2Ni_ (17)) (2:17) as-cast alloys. The sample hardened at 1130 ° C under argon was mainly of hexagonal 2:17 phase (defect type). It corresponds to a low intrinsic coercivity. There is also a small amount of Sm_2O_3. After 750 ℃, 600 ℃ multi-order aging quenched samples, found in the hexagonal 2:17 base phase, accompanied by the emergence of AM structure, precipitated a small amount of diamond 2:17 phase. It corresponds to a high intrinsic coercivity. Under the protection of hydrogen, the sample hardened at 1130 ° C showed that its intrinsic coercivity was also quite high. The precipitation of the second phase was also observed at this time. The second phase is precipitated at the optimum size, resulting in nodal pinning of the domain walls, thus contributing significantly to the intrinsic coercivity.