Effects of the quenching rate and annealing temperature on hard magnetic properties of rapidly quenched Co_(84-x)B_(x)Zr_(16)and Co_(82-x)Fe_(x)Zr_(18)alloys were studied.The B-or Fe-content dependence of room tempera...Effects of the quenching rate and annealing temperature on hard magnetic properties of rapidly quenched Co_(84-x)B_(x)Zr_(16)and Co_(82-x)Fe_(x)Zr_(18)alloys were studied.The B-or Fe-content dependence of room temperature coercivity H_(c),remanence B_(r) and maximum energy product(BH)_(max) are obtained.The H_(c) is suggested to originate from the microstructure with the optimal grain size.展开更多
Ma.gnetiza.tion,Curie teiiiperti.ture mid crystallization temperature measurements for amorphous(Fe_(1-x)Nd_(x))_(100-y)B_(y) iilloys with y=6,18.5 and 25 have been made.Spon-taneous magnetization shows a monotonic de...Ma.gnetiza.tion,Curie teiiiperti.ture mid crystallization temperature measurements for amorphous(Fe_(1-x)Nd_(x))_(100-y)B_(y) iilloys with y=6,18.5 and 25 have been made.Spon-taneous magnetization shows a monotonic decrease with x,and the noncollinear spin structures have been proposed to expluin the observed results.The composition dependence of Curie tenipertitiire is exphtined by the average niolecular-field model.The substitu lion of siim.ll N<1 for Fc is found to have a strong enha.nccinent of the theriiml stability in amorphous Fe-Nd-B alloys.展开更多
Magnetic properties and crystallization of amorphous Fe_(62)Co_(15.5)Nd_(4)B_(18.5) alloy are studied.The Curie temperature of the present sample is 127K higher than that of amorphous Fe_(77.5)Nd_(4)B_(18.5) alloy,but...Magnetic properties and crystallization of amorphous Fe_(62)Co_(15.5)Nd_(4)B_(18.5) alloy are studied.The Curie temperature of the present sample is 127K higher than that of amorphous Fe_(77.5)Nd_(4)B_(18.5) alloy,but their crystallization temperature is compatible with each other.A coercive field of 2.34kOe,a remanence of 12.3kG and an energy product of 11.6MGOe are obtained at room temperature in the Fe_(62)Co_(15.5)Nd_(4)B_(18.5) alloy annealed at 650°C.The 15.5at.%-Co substitution for Fe results in an increase of about 1l0K in Tc of 2:14:1 phase.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 crystallization of amorphous Co_(84-x)BxZr_(16) alloys and the influence of heat treatment on its hard magnetic properties are studied.The dependence of B-content on crystallization temperature of the samples is d...The crystallization of amorphous Co_(84-x)BxZr_(16) alloys and the influence of heat treatment on its hard magnetic properties are studied.The dependence of B-content on crystallization temperature of the samples is determined from differential scanning calorimetric(DSC)traces.The intrinsic coercivities iHc are found to increase with increasing annealing temperature and go through a mazimum then to lower values.A coercivity of 2.7kOe and an energy product of 4.0MGOe are obtained at room temperature in Co_(82)B_(2)Zr_(16) alloy annealed at 660°C for a short time.These alloys would be expected as an applicable mate rid for permanent magnet.展开更多
In the reduced curves of electronic resistivity and thermomagnetic measurement of the amorphous alloys,(Fe_(1-x)Ni_(x))_(84)B_(16) with 0.02<x<0.08,preheated to a temperature higher than that of crystallization,...In the reduced curves of electronic resistivity and thermomagnetic measurement of the amorphous alloys,(Fe_(1-x)Ni_(x))_(84)B_(16) with 0.02<x<0.08,preheated to a temperature higher than that of crystallization,an anomalous abruption at about 150℃ was observed.The results of differential thermal analysis(DTA)and of X-ray diffraction show that after crystallization of the amorphous alloys(Fe_(1-x)Ni_(x))_(84)B_(16) the anomalous abruption can be attributed to the martensitic transformation of γ Fe(Ni)to α Fe(Ni).展开更多
基金Supported by the National Natural Science Foundation of China.
文摘Effects of the quenching rate and annealing temperature on hard magnetic properties of rapidly quenched Co_(84-x)B_(x)Zr_(16)and Co_(82-x)Fe_(x)Zr_(18)alloys were studied.The B-or Fe-content dependence of room temperature coercivity H_(c),remanence B_(r) and maximum energy product(BH)_(max) are obtained.The H_(c) is suggested to originate from the microstructure with the optimal grain size.
文摘Ma.gnetiza.tion,Curie teiiiperti.ture mid crystallization temperature measurements for amorphous(Fe_(1-x)Nd_(x))_(100-y)B_(y) iilloys with y=6,18.5 and 25 have been made.Spon-taneous magnetization shows a monotonic decrease with x,and the noncollinear spin structures have been proposed to expluin the observed results.The composition dependence of Curie tenipertitiire is exphtined by the average niolecular-field model.The substitu lion of siim.ll N<1 for Fc is found to have a strong enha.nccinent of the theriiml stability in amorphous Fe-Nd-B alloys.
文摘Magnetic properties and crystallization of amorphous Fe_(62)Co_(15.5)Nd_(4)B_(18.5) alloy are studied.The Curie temperature of the present sample is 127K higher than that of amorphous Fe_(77.5)Nd_(4)B_(18.5) alloy,but their crystallization temperature is compatible with each other.A coercive field of 2.34kOe,a remanence of 12.3kG and an energy product of 11.6MGOe are obtained at room temperature in the Fe_(62)Co_(15.5)Nd_(4)B_(18.5) alloy annealed at 650°C.The 15.5at.%-Co substitution for Fe results in an increase of about 1l0K in Tc of 2:14:1 phase.
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 crystallization of amorphous Co_(84-x)BxZr_(16) alloys and the influence of heat treatment on its hard magnetic properties are studied.The dependence of B-content on crystallization temperature of the samples is determined from differential scanning calorimetric(DSC)traces.The intrinsic coercivities iHc are found to increase with increasing annealing temperature and go through a mazimum then to lower values.A coercivity of 2.7kOe and an energy product of 4.0MGOe are obtained at room temperature in Co_(82)B_(2)Zr_(16) alloy annealed at 660°C for a short time.These alloys would be expected as an applicable mate rid for permanent magnet.
文摘In the reduced curves of electronic resistivity and thermomagnetic measurement of the amorphous alloys,(Fe_(1-x)Ni_(x))_(84)B_(16) with 0.02<x<0.08,preheated to a temperature higher than that of crystallization,an anomalous abruption at about 150℃ was observed.The results of differential thermal analysis(DTA)and of X-ray diffraction show that after crystallization of the amorphous alloys(Fe_(1-x)Ni_(x))_(84)B_(16) the anomalous abruption can be attributed to the martensitic transformation of γ Fe(Ni)to α Fe(Ni).
