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Magnetostriction Coefficient of Amorphous Fe ₇₈Si ₉B ₁₃ Under Two Distinctive Treatment

GUO Hong, CHEN Ming-ming

Abstract （515）

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Amorphous alloy sample Fe ₇₈Si ₉B ₁₃ is disposed by low frequency pulsating magnetic field and isothermic annealing, measuring magnetostriction coefficient by self-made magnetostriction coefficient measuring system. Results showed that both treatment process decreased the saturation magnetostriction coefficient λ _s of sample, λ _s is related with annealing time t and it reached minimal value 4.952×10 ^-5 when annealing under 300℃ for 40min. Saturation magnetostriction coefficient λs and low-frequency pulsed magnetic field strength Hp is nonlinear relationship, λ _s has a choice on the disposing parameters of pulsed magnetic field, λs reach minimal value 2.70×10 ^-5 when Hp equals to 19 900 A/m, pulsing frequency equals to 30Hz and processing time t equals to 240s. The impact of saturation magnetostriction coefficient by low frequency pulsed magnetic field is significantly greater than annealing.

2012, 32 (4): 92-94. DOI: 10.3696/j.issn.1672-6952.2012.04.024

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M-ssbauer Spectra ofCo68.15Fe4.35Si12.5B15 by Low Frequency Pulse Magnetic Field

ZHANG Lei， GUO Hong

Abstract （348）

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Amorphous alloys ofCo68.15Fe4.35Si12.5B15  were treated by low frequency pulse magnetic field．The microstructure changes of amorphous specimens before and after treatment were observed by Mssbauer spectra and TEM．The results show that the nanocrystallization of amorphous alloy ofCo68.15Fe4.35Si12.5B15  can occur at low frequency pulse magnetic field．The precipitation content of the nanocrystalline phase α-Fe(Si) with bcc crystal structure is about 2.743％~23.960％，the grain size is 2~10 nm，and the quantity of crystallization have relation with the magnetic field intensity and pulse frequency.

2010, 30 (4): 76-79. DOI: 10.3696/j.issn.1672-6952.2010.04.021

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Calculation of Transverse Permeability for Magnetic Ribbons

GUO Hong, CHAO Yue-sheng

Abstract （336）

PDF （202KB）（233）

Differential operator elimination method was applied to solve the Maxwell's system of partial differential equations obtain to the general expressions of transverse permeability for magnetic ribbons. The expressions of transverse permeability for magnetic ribbons were found out in driving current full frequency section with the Landau-Lifshite equation. The results show that under the alternating magnetization the transverse permeability of ribbons relate to external magnetic field and driver electric current frequency，and has be orientation-related relativity as well.

2009, 29 (3): 85-88.

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Giant Magnetic Impedance Effect on Nano-Crystallization of Amorphous Alloy Co60.15Fe4.35Si12.5B15 Caused by Lower Frequency Pulse Magnetic Field

JIN Ying, GUO Hong

Abstract （336）

PDF （171KB）（238）

Nano-crystallization of amorphous alloy Co60.15Fe4.35Si12.5B15 can be realized with the process of low-frequency pulsating magnetic field. In the process of crystallization, temperature rising is less than 5 ℃, which can prevent efficiently material from getting fragile and obtain the nano-crystallization soft magnetic properties superior to routine isothermal annealing. The larger GMI effect was observed in the experiment, and the best driving frequency is 2 MHz and the transverse anisotropy field is 0.9 kA/m.

2008, 28 (3): 87-88.