Microstructure formed in the Fe-Ni-Co-Al-Cu-Ti permanent magnetic alloy with different treatments was studied by means of TEM observation, XRD method and SAXS technology. The results indicated that spinodal decomposi...Microstructure formed in the Fe-Ni-Co-Al-Cu-Ti permanent magnetic alloy with different treatments was studied by means of TEM observation, XRD method and SAXS technology. The results indicated that spinodal decomposition and orderiing transformation coexisted in the alloy and spinodal decomposition was completed in a short time. The ratio of component of spinodal and ordered microstructure was dependent on the cooling rate. The variation of gyration radius RG of the rod-like precipitates could be accounted for by the different growth modes of the precipitates related to strain energy and interface energy.展开更多
The research is carried out through specification measurement of magnetic property, photo analysis of electronic microscope, metallographic analysis, micro hard and so on means. The initial researches have been d...The research is carried out through specification measurement of magnetic property, photo analysis of electronic microscope, metallographic analysis, micro hard and so on means. The initial researches have been done about the influence on material property by solid solution treatment, heat magnetic treatment and aging treatment technology of the low cobalt Fe Cr Co alloy. Therefore, better productive technologies have been found.展开更多
The magnetic properties of (Nd_(0.9)Dy_(0.1))_(16)Co_(5)Fe_(70)Nb_(2)B_(7) permanent magnetic alloy prepared by powder metallurgy are:Br=1.08T,_(1)H_(C)=1620kA/m,(BH)_(max)=208kJ/m^(3).The behaviour of Nb in this allo...The magnetic properties of (Nd_(0.9)Dy_(0.1))_(16)Co_(5)Fe_(70)Nb_(2)B_(7) permanent magnetic alloy prepared by powder metallurgy are:Br=1.08T,_(1)H_(C)=1620kA/m,(BH)_(max)=208kJ/m^(3).The behaviour of Nb in this alloy was studied by joint methods of dynamic observation by high voltage electron microscope(HVEM)and Mossbauer effects.With Nb and Co substituting parts of Fe and adding a little Dy,practical magnetic alloy with excellent properties can be obtained.The thermal stability of it is 80 ℃ higher than that of ternary Nd-Fe-13 magnet.The study shows that adding Nb into Nd-Fe-B can make the intrinsic coercivity appear peak value at about Nb=2%(in mole fraction).Nb mainly enters into Nd-rich and B-rich phases,a little into Nd_(2)Fe_(14)B phase.展开更多
A dynamic observation on the Sm (Co, Cu, Fe, Zr)_(7.4) permanent magnetic alloy with a 1000 kV HVEM and a study on the effect of Zr by Mossbauer effect are carried out. The magnetic property of the above magnets by po...A dynamic observation on the Sm (Co, Cu, Fe, Zr)_(7.4) permanent magnetic alloy with a 1000 kV HVEM and a study on the effect of Zr by Mossbauer effect are carried out. The magnetic property of the above magnets by powder metallurgy is Br=1.12 T, _iH_c=1078 kA/m, (BH)_(max)=243.6 kJ/m^3. It is found that the centers of the cellular structure. which plays an important role for _iH_c, form at 460℃ and grow up during 5000℃ to 700℃. The intrinsic coercivity of the alloy rises up with the gradual perfection, the size and amount increment of cellular structure. The Mossbauer experiment showed the addition of Zr induced atoms to enter into 2:17 phase from 1:5 phase, which raised the content and magnetic difference of the two phases. Adding Zr speeded up Fe atom to move to Co_3 crystal position from Co_1 position, hence raised the single-axis anisotropy of the alloy. The two effects are both beneficial for the rise of _iH_c.展开更多
文摘Microstructure formed in the Fe-Ni-Co-Al-Cu-Ti permanent magnetic alloy with different treatments was studied by means of TEM observation, XRD method and SAXS technology. The results indicated that spinodal decomposition and orderiing transformation coexisted in the alloy and spinodal decomposition was completed in a short time. The ratio of component of spinodal and ordered microstructure was dependent on the cooling rate. The variation of gyration radius RG of the rod-like precipitates could be accounted for by the different growth modes of the precipitates related to strain energy and interface energy.
文摘The research is carried out through specification measurement of magnetic property, photo analysis of electronic microscope, metallographic analysis, micro hard and so on means. The initial researches have been done about the influence on material property by solid solution treatment, heat magnetic treatment and aging treatment technology of the low cobalt Fe Cr Co alloy. Therefore, better productive technologies have been found.
基金Supported by the State Key Laboratory of Magnetism,Chinese Academy of Sciences。
文摘The magnetic properties of (Nd_(0.9)Dy_(0.1))_(16)Co_(5)Fe_(70)Nb_(2)B_(7) permanent magnetic alloy prepared by powder metallurgy are:Br=1.08T,_(1)H_(C)=1620kA/m,(BH)_(max)=208kJ/m^(3).The behaviour of Nb in this alloy was studied by joint methods of dynamic observation by high voltage electron microscope(HVEM)and Mossbauer effects.With Nb and Co substituting parts of Fe and adding a little Dy,practical magnetic alloy with excellent properties can be obtained.The thermal stability of it is 80 ℃ higher than that of ternary Nd-Fe-13 magnet.The study shows that adding Nb into Nd-Fe-B can make the intrinsic coercivity appear peak value at about Nb=2%(in mole fraction).Nb mainly enters into Nd-rich and B-rich phases,a little into Nd_(2)Fe_(14)B phase.
基金Project supported by the State Key Laboratory of Magnetism Institute of Physics, Academia Sinica.
文摘A dynamic observation on the Sm (Co, Cu, Fe, Zr)_(7.4) permanent magnetic alloy with a 1000 kV HVEM and a study on the effect of Zr by Mossbauer effect are carried out. The magnetic property of the above magnets by powder metallurgy is Br=1.12 T, _iH_c=1078 kA/m, (BH)_(max)=243.6 kJ/m^3. It is found that the centers of the cellular structure. which plays an important role for _iH_c, form at 460℃ and grow up during 5000℃ to 700℃. The intrinsic coercivity of the alloy rises up with the gradual perfection, the size and amount increment of cellular structure. The Mossbauer experiment showed the addition of Zr induced atoms to enter into 2:17 phase from 1:5 phase, which raised the content and magnetic difference of the two phases. Adding Zr speeded up Fe atom to move to Co_3 crystal position from Co_1 position, hence raised the single-axis anisotropy of the alloy. The two effects are both beneficial for the rise of _iH_c.
