The dipolar interactions are investigated through the asymmetric magneto-impedance in FINEMET/SiO_(2)/FePd composite ribbons.The interface between the hard(FePd layer)phase and soft(FINEMET ribbon)phase is coherent by...The dipolar interactions are investigated through the asymmetric magneto-impedance in FINEMET/SiO_(2)/FePd composite ribbons.The interface between the hard(FePd layer)phase and soft(FINEMET ribbon)phase is coherent by SiO_(2)layer in FINEMET/SiO_(2)/FePd composite ribbons,which effectively induces dipolar interactions.The contribution of dipolar interaction to the bias field(Hb)by asymmetrical giant magneto-impedance and magnetic properties is analyzed.The results show that Hb response decreases with the increase of the SiO_(2)layer thickness,indicating that the linear region near-zero field can be tuned by the thickness of SiO_(2)layer.These results allow the GMI ratio(58%)and characteristic frequency(500 kHz)to be optimized.The transverse and longitudinal magnetic domain structures of FINEMET ribbon and FePd film are confirmed,respectively.The composite ribbons with high GMI ratio and low frequency can be applied to linear magnetic sensors.展开更多
采用磁控溅射的方法制备了Si_3N_4/FePd/Si_3N_4三层膜,研究了非磁性材料Si_3N_4作为插入层对磁记录FePd薄膜结构与磁性能的影响。结果表明,热处理后Si_3N_4分布在FePd纳米颗粒之间,抑制了FePd晶粒的生长,与纯FePd薄膜相比,Si_3N_4/FePd...采用磁控溅射的方法制备了Si_3N_4/FePd/Si_3N_4三层膜,研究了非磁性材料Si_3N_4作为插入层对磁记录FePd薄膜结构与磁性能的影响。结果表明,热处理后Si_3N_4分布在FePd纳米颗粒之间,抑制了FePd晶粒的生长,与纯FePd薄膜相比,Si_3N_4/FePd/Si_3N_4薄膜的颗粒明显得到细化;通过添加Si_3N_4层,FePd薄膜的晶体学参数c/a从0.960减小到0.946,表明Si_3N_4可以有效促进FePd薄膜的有序化进程,同时提升了矫顽力和剩磁比,分别提高到249 k A/m、0.86;随着600℃退火时间的进一步延长,添加Si_3N_4的薄膜磁性没有迅速下降,在较宽的热处理时间范围内磁性能保持在比较高的水平,提高了抗热影响的能力。Si_3N_4作为插入层对FePd薄膜的磁性能具有较大的提升作用,这对磁记录薄膜的发展具有重要意义。展开更多
A series of FePd based alloy films were deposited on glass substrates by DC magnetron sputtering. The Ag toplayer effect was studied using FePd（67.5 nm）/Ag（3.875, 7.75, 15.50, 31 and 38.75 nm） films annealed at 6...A series of FePd based alloy films were deposited on glass substrates by DC magnetron sputtering. The Ag toplayer effect was studied using FePd（67.5 nm）/Ag（3.875, 7.75, 15.50, 31 and 38.75 nm） films annealed at 600 ℃ for different time in order to find the role of the Ag toplayer in disorder-order of FePd film. The results show that the Ag toplayer can accelerate the phase transition from FCC to FCT in films. The magnetic easy axis of the crystallites in this film is in-plane of substrate. The Ag toplayer can greatly enhance the coercive of FePd films. When the thickness of Ag is equal to 31 nm, the film has a very large in-plane coercivity of 2.8 kOe and a very low out-of-plane coercivity of 1.04 kOe.展开更多
以对环境友好的Fe(acac)_3和Pd(acac)_2作为主反应物,PEG-400为还原剂,通过简易的溶剂热法制备了FePd纳米颗粒,并对其磁性能和电催化活性进行了研究。结果表明:合成态的样品中FePd纳米颗粒为fcc相,其磁性能表现为超顺磁性,并对乙醇氧化...以对环境友好的Fe(acac)_3和Pd(acac)_2作为主反应物,PEG-400为还原剂,通过简易的溶剂热法制备了FePd纳米颗粒,并对其磁性能和电催化活性进行了研究。结果表明:合成态的样品中FePd纳米颗粒为fcc相,其磁性能表现为超顺磁性,并对乙醇氧化表现出了一定的电催化活性。经过95%Ar+5%H_2气氛下热处理后,FePd纳米颗粒从fcc相转变为fct相,磁性能转变为硬磁性,内禀矫顽力达到1.8 k Oe,而且样品对乙醇氧化的电催化活性较之热处理前明显提高,峰值电流密度达26.6 m A/mg。展开更多
采用直流磁控溅射法制备Dyx(Fe47.5Pd52.5)100-x(x=0,2.2,3.2,4.4,5.6)薄膜,X射线衍射实验结果表明:添加稀土元素Dy可以大幅缩短从无序的fcc相转变为有序的fct相的退火时间和退火温度,增加相转变的驱动力;此外适当添加Dy元素还具有细化...采用直流磁控溅射法制备Dyx(Fe47.5Pd52.5)100-x(x=0,2.2,3.2,4.4,5.6)薄膜,X射线衍射实验结果表明:添加稀土元素Dy可以大幅缩短从无序的fcc相转变为有序的fct相的退火时间和退火温度,增加相转变的驱动力;此外适当添加Dy元素还具有细化晶粒的作用,晶粒尺寸可达到12~31 nm,适当的晶粒尺寸有利于晶粒之间的交换耦合作用。薄膜的磁滞回线表明:矫顽力Hc与剩磁比Mr/Ms随Dy含量的增加而先急剧增加后减小,当稀土含量x=3.2时,矫顽力的最大值为3.27 k Oe。随着退火温度的增加,矫顽力的变化也是先增加后下降,并且在Ta=550℃时达到最大。展开更多
基金Project supported by the Natural Science Foundation of Shandong Province,China(Grant No.ZR2022MF276)the Major Innovation Fund of Qilu University of Technology(Shandong Academy of Science),China(Grant No.2022JBZ02-02)+1 种基金the Fund from Shanghai Science and Technology Commission,China(Grant No.22142200900)the Natural Science Foundation of Guangxi Zhuang Autonomous Region,China(Grant No.2019GXNSFAA245056).
文摘The dipolar interactions are investigated through the asymmetric magneto-impedance in FINEMET/SiO_(2)/FePd composite ribbons.The interface between the hard(FePd layer)phase and soft(FINEMET ribbon)phase is coherent by SiO_(2)layer in FINEMET/SiO_(2)/FePd composite ribbons,which effectively induces dipolar interactions.The contribution of dipolar interaction to the bias field(Hb)by asymmetrical giant magneto-impedance and magnetic properties is analyzed.The results show that Hb response decreases with the increase of the SiO_(2)layer thickness,indicating that the linear region near-zero field can be tuned by the thickness of SiO_(2)layer.These results allow the GMI ratio(58%)and characteristic frequency(500 kHz)to be optimized.The transverse and longitudinal magnetic domain structures of FINEMET ribbon and FePd film are confirmed,respectively.The composite ribbons with high GMI ratio and low frequency can be applied to linear magnetic sensors.
文摘采用磁控溅射的方法制备了Si_3N_4/FePd/Si_3N_4三层膜,研究了非磁性材料Si_3N_4作为插入层对磁记录FePd薄膜结构与磁性能的影响。结果表明,热处理后Si_3N_4分布在FePd纳米颗粒之间,抑制了FePd晶粒的生长,与纯FePd薄膜相比,Si_3N_4/FePd/Si_3N_4薄膜的颗粒明显得到细化;通过添加Si_3N_4层,FePd薄膜的晶体学参数c/a从0.960减小到0.946,表明Si_3N_4可以有效促进FePd薄膜的有序化进程,同时提升了矫顽力和剩磁比,分别提高到249 k A/m、0.86;随着600℃退火时间的进一步延长,添加Si_3N_4的薄膜磁性没有迅速下降,在较宽的热处理时间范围内磁性能保持在比较高的水平,提高了抗热影响的能力。Si_3N_4作为插入层对FePd薄膜的磁性能具有较大的提升作用,这对磁记录薄膜的发展具有重要意义。
基金Funded by the National Basic Research Program of China(973 Program)(No.2014CB643703)National Natural Science Foundation of China(Nos.51261004,61571142,51562004 and 51461012)+1 种基金National Natural Science Foundation of Guangxi(Nos.2016GXNSFAA380030 and 2016GXNSFFA380007)the Guangxi Key Laboratory of Information Materials Foundation(Nos.161008-Z and 171004-Z)
文摘A series of FePd based alloy films were deposited on glass substrates by DC magnetron sputtering. The Ag toplayer effect was studied using FePd（67.5 nm）/Ag（3.875, 7.75, 15.50, 31 and 38.75 nm） films annealed at 600 ℃ for different time in order to find the role of the Ag toplayer in disorder-order of FePd film. The results show that the Ag toplayer can accelerate the phase transition from FCC to FCT in films. The magnetic easy axis of the crystallites in this film is in-plane of substrate. The Ag toplayer can greatly enhance the coercive of FePd films. When the thickness of Ag is equal to 31 nm, the film has a very large in-plane coercivity of 2.8 kOe and a very low out-of-plane coercivity of 1.04 kOe.
基金National Key Basic Research Development Program of China("973" Program)(2014CB643703)National Natural Science Foundation of China(51261004,51461012)+1 种基金Natural Science Foundation of Guangxi(2013GXNSFBA019242)the Research Foundation of Guangxi Key Laboratory of Information Materials(131003-Z,131007-Z)
文摘以对环境友好的Fe(acac)_3和Pd(acac)_2作为主反应物,PEG-400为还原剂,通过简易的溶剂热法制备了FePd纳米颗粒,并对其磁性能和电催化活性进行了研究。结果表明:合成态的样品中FePd纳米颗粒为fcc相,其磁性能表现为超顺磁性,并对乙醇氧化表现出了一定的电催化活性。经过95%Ar+5%H_2气氛下热处理后,FePd纳米颗粒从fcc相转变为fct相,磁性能转变为硬磁性,内禀矫顽力达到1.8 k Oe,而且样品对乙醇氧化的电催化活性较之热处理前明显提高,峰值电流密度达26.6 m A/mg。
基金supported by the National Natural Science Foundation of China(81571693,82171950,81871361,82271997,and 82003182)the National Science Foundation for Young Scientists of China(82102085)+4 种基金UNSW-CAS Collaborative Research Seed Program(GJHZ2072)Shanghai Science and Technology Program(21010500100,22140901700,22DZ2204700,and 22142202200)Basic Research Program of Shanghai Municipal Government(21JC1406002)Shanghai Municipal Health Commission(202140250)Pudong Health Bureau of Shanghai(PWRl201806)。
文摘采用直流磁控溅射法制备Dyx(Fe47.5Pd52.5)100-x(x=0,2.2,3.2,4.4,5.6)薄膜,X射线衍射实验结果表明:添加稀土元素Dy可以大幅缩短从无序的fcc相转变为有序的fct相的退火时间和退火温度,增加相转变的驱动力;此外适当添加Dy元素还具有细化晶粒的作用,晶粒尺寸可达到12~31 nm,适当的晶粒尺寸有利于晶粒之间的交换耦合作用。薄膜的磁滞回线表明:矫顽力Hc与剩磁比Mr/Ms随Dy含量的增加而先急剧增加后减小,当稀土含量x=3.2时,矫顽力的最大值为3.27 k Oe。随着退火温度的增加,矫顽力的变化也是先增加后下降,并且在Ta=550℃时达到最大。
