The effects of the annealing temperature and time on the structure and magnetic properties of the sputtered BiDy-iron garnet films were investigated.X-ray diffraction analysis shows that the as-sputtered films are amo...The effects of the annealing temperature and time on the structure and magnetic properties of the sputtered BiDy-iron garnet films were investigated.X-ray diffraction analysis shows that the as-sputtered films are amorphous.After annealing at about 550℃,amorphous films crystallize into the garnet phase and an unknown phase.The intensity of the unknown phase decreases with increasing annealing temperature and time and vanishes at 650℃for 30min.It is found that the unknown phase has a large influence on the half-width of the(420)x-ray diffraction peak.The as-sputtered films have a very small magnetization of about 1 emu/g at room temperature.When films are annealed above 570℃,the magnetization increases rapidly with increasing annealing temperature and time.展开更多
The magnetization curves at 1.5K and Curie temperature of amorphow (Fe_(100-x)B_(x))_(88)Nd_(12±ε) alloys were measured.Their spontaneous magnetizations is explained by a noncollinear structure.The average magne...The magnetization curves at 1.5K and Curie temperature of amorphow (Fe_(100-x)B_(x))_(88)Nd_(12±ε) alloys were measured.Their spontaneous magnetizations is explained by a noncollinear structure.The average magnetic moment μ_(Fe) per Fe atom decreases monotonically with increasing x,and becomes more rapid when x>24.The B content dependence of Curie temperature shows a mazimum at x=15.At x<15,the increase of T_(c) with x may be attributed to the indirect exchange interactions between Fe-Fe atoms.展开更多
The magnetization curves at 1.5K and thermomagnetization curves in the fields of about 450e for amorphous Fe_(90-x)Si_(x)Zr_(10)(x=0,4,7 and 10)alloys prepared by the drum spinning technique are measured with an eztra...The magnetization curves at 1.5K and thermomagnetization curves in the fields of about 450e for amorphous Fe_(90-x)Si_(x)Zr_(10)(x=0,4,7 and 10)alloys prepared by the drum spinning technique are measured with an eztracting sample magnetometer.At low Si concentration the amorphous Fe_(90-x)Si_(x)Zr_(10) alloys exhibit a large value of the high-field susceptibility,but the average magnetic moment per Fe atomμFe,and the Curie temperature,Tc,are quite small,compared with amorphous Fe_(87-x)Si_(x)B_(13) alloys.This unusual behavior could be explained in terms of the presence of the antiferromagnetic state.展开更多
The hysteresis loop and Mdssbauer spectrum of the heat treated Nd_(3)Fe_(81)B_(16) alloy ribbons annealing at 660℃ for lOmin.have been measured.A coercive field of about 2kOe and an energy product of about 8MGOe are ...The hysteresis loop and Mdssbauer spectrum of the heat treated Nd_(3)Fe_(81)B_(16) alloy ribbons annealing at 660℃ for lOmin.have been measured.A coercive field of about 2kOe and an energy product of about 8MGOe are obtained at room temperature.X-ray diffraction and Mdssbauer spectrum analyses show that the high coercivity may originate from the Fe_(3)B phase containing Nd.The value of remanence and energy product in this alloy are much higher than those of anisotropic BaFe_(12)O_(19) ferrite.It may be used as a cheap permanent magnet.展开更多
基金the National Natural Science Foundation of ChinaState Key Laboratory of Magnetism,Institute of Physics,Chinese Academy of Sciences.
文摘The effects of the annealing temperature and time on the structure and magnetic properties of the sputtered BiDy-iron garnet films were investigated.X-ray diffraction analysis shows that the as-sputtered films are amorphous.After annealing at about 550℃,amorphous films crystallize into the garnet phase and an unknown phase.The intensity of the unknown phase decreases with increasing annealing temperature and time and vanishes at 650℃for 30min.It is found that the unknown phase has a large influence on the half-width of the(420)x-ray diffraction peak.The as-sputtered films have a very small magnetization of about 1 emu/g at room temperature.When films are annealed above 570℃,the magnetization increases rapidly with increasing annealing temperature and time.
文摘The magnetization curves at 1.5K and Curie temperature of amorphow (Fe_(100-x)B_(x))_(88)Nd_(12±ε) alloys were measured.Their spontaneous magnetizations is explained by a noncollinear structure.The average magnetic moment μ_(Fe) per Fe atom decreases monotonically with increasing x,and becomes more rapid when x>24.The B content dependence of Curie temperature shows a mazimum at x=15.At x<15,the increase of T_(c) with x may be attributed to the indirect exchange interactions between Fe-Fe atoms.
文摘The magnetization curves at 1.5K and thermomagnetization curves in the fields of about 450e for amorphous Fe_(90-x)Si_(x)Zr_(10)(x=0,4,7 and 10)alloys prepared by the drum spinning technique are measured with an eztracting sample magnetometer.At low Si concentration the amorphous Fe_(90-x)Si_(x)Zr_(10) alloys exhibit a large value of the high-field susceptibility,but the average magnetic moment per Fe atomμFe,and the Curie temperature,Tc,are quite small,compared with amorphous Fe_(87-x)Si_(x)B_(13) alloys.This unusual behavior could be explained in terms of the presence of the antiferromagnetic state.
文摘The hysteresis loop and Mdssbauer spectrum of the heat treated Nd_(3)Fe_(81)B_(16) alloy ribbons annealing at 660℃ for lOmin.have been measured.A coercive field of about 2kOe and an energy product of about 8MGOe are obtained at room temperature.X-ray diffraction and Mdssbauer spectrum analyses show that the high coercivity may originate from the Fe_(3)B phase containing Nd.The value of remanence and energy product in this alloy are much higher than those of anisotropic BaFe_(12)O_(19) ferrite.It may be used as a cheap permanent magnet.
