退火对非晶合金磁特性及铁心磁致振动的影响

为研究退火处理对非晶合金磁特性及非晶铁心振动的影响,采用磁特性测量设备对退火前非晶带材及退火后非晶铁心的磁化特性和磁致伸缩特性进行了测量,基于测量数据建立了非晶合金卷形铁心磁-机械多物理场耦合模型,计算得出退火前后两种状态铁心各处的磁通密度分布及振动情况,并与样机振动测量数据进行了比较。结果表明:退火可提高非晶合金饱和磁感应强度,改善磁导率,并可减小磁致伸缩系数,从而有效地抑制变压器铁心的振动。     

Ni合金化对Finemet合金热稳定性及软磁性能的影响

通过铜辊甩带法制备了成分为Fe_73.5-xSi_13.5B₉Cu₁Nb₃Ni_x(x=0、1、2、3)的非晶带材,并对其进行退火处理。利用XRD、DSC、VSM和软磁直流测试仪等对带材的相结构、热稳定性以及软磁性能进行测试分析。结果表明,所制备合金带材淬火态下均为完全非晶结构,经560 ℃保温60 min退火处理后,合金中形成了非晶和α-Fe(Si)纳米晶双相共存结构。随着Ni含量的增加,整体上非晶带材的一级起始晶化温度T_s1和二级起始晶化温度T_s2先减小后增大,两级起始晶化温度之差ΔT_s整体呈下降的趋势,由166.0 ℃下降至132.8 ℃,热稳定性降低。淬火态下,Ni元素的添加使得非晶带材的软磁性能有所恶化。经退火处理后,带材的软磁性能明显提升,当Ni含量x=1时,具有较好的软磁性能,其饱和磁化强度为157.7 emu/g,矫顽力为6.8 Oe。     

FeCoNiSiB非晶合金感生各向异性对磁性能的影响

研究了恒温张力退火和横磁退火工艺对FeCoNiSiB非晶合金各向异性及磁性能的影响。结果表明,合金经恒温张力退火后表现出高直流偏置性能和高损耗的特点,而经横磁退火后具有优异的综合软磁性能,即具有高直流偏置能力的同时具有低损耗的特点。其中,恒温张力退火过程中提高退火温度时合金直流偏置能力增加,550 ℃下张力退火5 min的直流偏置场强度H_0.98为195 A/m,对应的损耗值P_cm为7255 W/kg;而经450 ℃横磁退火后,合金直流偏置场强度H_0.98可达374 A/m,对应的损耗值P_cm仅为200 W/kg。除此之外,经恒温张力退火和横磁退火后FeCoNiSiB非晶合金内部均形成180°条形磁畴结构,但其磁化矢量方向分别平行和垂直于磁化方向。     

厚度减薄对Fe_(81)B_(13.5)Si_(3.5)C_2非晶薄带磁各向异性和磁矩取向分布的影响

急冷法制备的非晶软磁材料的实用磁性与其磁各向异性和磁矩取向分布密切相关。大量研究表明,急冷状态的过渡金属-类金属非晶合金薄带里的磁畴结构和磁矩取向主要取决于淬火急冷内应力。Becker通过磁化测量发现,表面层去除和厚度减薄对急冷内应力系统没有影响。Takahashi等的磁转矩研究表明,急冷态非晶薄带2个表面附近的磁各向异性最大。对急冷态非晶薄带的Moss-bauer研究表明,磁矩取向主要分布在薄带平     

对非晶质合金工件进行退火处理的方法

本发明涉及一种对非晶质合金工件进行退火处理的方法,其包括下列步骤：提供具有纵向轴线和合金成分的未经退火处理的非晶质合金工件,以这样的方式选择合金成分．即当所述非晶质合金工件在360℃下退火6s时在所述非晶质合金工件中产生大于0．04Oe／MPa的应力感应各向异性以及当在退火过程中沿着所述纵向轴线施加张应力时产生垂直于所述纵向轴线的易磁化轴线：以及将所述非晶质合金工件放置在高温区域中,并且没有不同于环境磁场的磁场,同时使所述非晶质合金经受沿着所述纵向轴线的张力作用以在所述非晶质合金工件中产生大于0．04Oe／MPa的所述各向异性和所述易磁化轴线。     

纳米晶软磁合金磁场退火效应研究进展

介绍了纳米晶软磁合金磁场退火后合金晶化行为和磁畴结构的变化。相对于无磁退火,磁场退火可以起到细化晶粒、提高纳米晶粒形核率的作用,从而使合金中晶体相所占的比重得到增加,软磁性能得到改善;磁场退火后,合金的磁畴结构中钉扎位消失,磁畴界面清晰,多沿外场方向分布。     

高饱和磁感Fe82Si3.8B13.9C0.3非晶铁芯的退火及浸漆工艺

研究了不同磁场退火和浸漆固化工艺对Fe₈₂Si_3.8B_13.9C_0.3非晶合金环形铁芯损耗和磁性能的影响,并与1K101合金铁芯进行了对比。结果表明:与1K101合金相比,Fe₈₂Si_3.8B_13.9C_0.3合金铁芯的最佳退火温度低于1K101合金,其中纵磁退火时达到最低,为330 ℃。纵磁退火Fe₈₂Si_3.8B_13.9C_0.3合金铁芯有着更高的饱和磁感应强度,B_{3500 A/m}=1.611 T。经350 ℃无磁场退火处理后,Fe₈₂Si_3.8B_13.9C_0.3合金铁芯的损耗P_{50 Hz, 1.4 T}=0.360 W/kg,稍高于1K101合金;经330 ℃纵磁退火处理后,Fe₈₂Si_3.8B_13.9C_0.3合金铁芯的损耗P_{50 Hz, 1.4 T}=0.257 W/kg,也高于1K101合金;经350 ℃横磁退火处理后损耗P_{50 Hz, 1.4 T}=0.163 W/kg,低于1K101合金。纵磁退火Fe₈₂Si_3.8B_13.9C_0.3合金铁芯经浸漆固化处理后,磁通密度B_{800 A/m}=1.341 T,比纵磁退火1K101合金浸漆固化铁芯高15%;纵磁退火且浸漆的Fe₈₂Si_3.8B_13.9C_0.3合金铁芯损耗低于1K101合金浸漆铁芯,且随着频率升高优势更加明显;当频率大于1000 Hz时,纵磁退火且浸漆的Fe₈₂Si_3.8B_13.9C_0.3合金铁芯的损耗值低于未浸漆铁芯。     

退火态Fe-Si-B非晶合金恒导磁性能研究

对退火Fe78Si9B13非晶合金部分晶化后的恒导磁特性进行了研究.结果表明,对于Fe78Si9B13非晶态铁基合金,随着退火温度的升高和退火时间的延长,晶化相逐渐增多.在适当温度经一定的时间退火后,初始磁导率和最大磁导率均逐渐减小,磁化曲线呈现出一定的线性关系,即合金呈现恒导磁特性.这种特性是由于表面晶化引起的体积收缩,给内部未晶化层施加了压应力,导致内部的磁畴横向排列,使合金产生恒导磁现象.     

Fe_5Co_(73)Si_(10)B_(12)非晶态合金磁各向异性与旋转磁场热处理效应

根据非晶态Fe_5Co_(73)Si_(10)B_(12)合金薄带不同方向磁化曲线与磁致伸缩曲线随退火状态的变化规律,发现Curie温度低于晶化温度的非晶态合金经旋转磁场热处理时,可以消除由于自发磁化场所感生的磁各向异性。初步分析和讨论了淬火态(制备)非晶态合金具有磁各向异性的原因。     

FeSiB-La合金的非晶形成能力和磁阻抗效应

将稀土La元素掺杂Fe78Si9B13合金,采用单辊法制备了FeSiB-La非晶带材,再将非晶带材在不同温度下进行退火处理。用DSC和XRD分析了带材的非晶形成能力和晶化行为,用阻抗分析仪测试了非晶带材的磁阻抗效应。结果表明,掺杂稀土La元素可提高带材的非晶形成能力,延缓带材中Fe-Si、Fe-B晶化相的析出,增强带材的热稳定性;Fe Si B-La非晶带材的磁阻抗效应随测试频率的升高和磁场强度的增大而增大;随退火温度升高,非晶带材的磁阻抗效应呈先增大后减小的趋势。     

Canted anisotropy magnetoelastic resonance material as sensors for electronic article surveillance system

A self-biasing magnetostrictive element for a magnetomechanical Electronic Article Surveillance (EAS) marker is fabricated by annealing a ribbon of ferromagnetic amorphous material (Co_47.4Fe_31.6Si₂Bi₁₉) in a presence of magnetic field applied in a transverse direction relative to the ribbon’s longitudinal axis, and then annealing in a presence of magnetic field applied in the direction of the longitudinal axis. The two-step annealed ribbon exhibits remanent magnetization along the longitudinal axis and has plural magnetic domains situated along the longitudinal axis. The magnetic orientation of each domain is canted by ± 03B8; < 90° from the ribbon axis with the direction of canting alternating from domain to domain. To obtain such a canted anisotropy, theoretical background for the calculation of the field strength (H) and canted angle (θ) is described.     

Magnetic properties,thermal stability,and structure of the nanocrystalline soft magnetic (Fe0.7Co0.3)88Hf2W2Mo2Zr1B4Cu1 alloy with induced magnetic anisotropy

The effect of magnitude of tensile stresses (σ) applied to the (Fe_0.7Co_0.3)₈₈Hf₂W₂Mo₂Zr₁B₄Cu₁ alloy with refractory-metal additions during its nanocrystallization at 620°C for 20 min on the magnetic properties, structure, and thermal stability of the alloy is studied. It has been found that, during the nanocrystallization of the alloy under the effect of tensile stresses of 6–250 MPa, longitudinal magnetic anisotropy with an easy magnetization axis parallel to the long size of ribbon is induced in the alloy. The thermal stability of magnetic properties of the alloy under study has been shown to be determined by the thermal stability of induced magnetic anisotropy and to depend on the magnitude of tensile stresses applied during nanocrystallizing annealing (NA). The better thermal stability of magnetic properties has been observed for the alloy subjected to NA at σ = 170 MPa. After annealing at 570°C for 25 h, the magnetic properties of the alloy are unchanged.     

Effect of electrolytic oxidation and hydrogenation on the magnetization distribution and magnetic properties of ribbons of amorphous soft magnetic iron-based alloys

The effect of electrolytic oxidation and hydrogenation on the magnetization distribution and magnetic properties of ribbons of amorphous soft magnetic iron-based alloys has been investigated on the example of the Fe₇₇Ni₁Si₉B₁₃ and Fe₈₁B₁₃Si₄C₂ alloys. The results of the investigation showed that hydrogenation and oxidation of the surface of the ribbon lead to changes in the magnetic properties, which agree with changes in its magnetic state. A decrease in the volume of domains with orthogonal magnetization observed upon oxidation is caused by the large effective diameter of oxygen atoms inducing a higher level of planar tensile stresses upon incorporation into the ribbon surface. A reduction (observed in both cases) in the volume fraction of domains with a planar magnetization oriented along the ribbon axis is connected with the appearance of pseudo-uniaxial tension in the plane of the ribbon across its axis, since the concentration of atoms incorporated into the surface is enchanced in this direction. The interaction of the surface of the ribbon at room temperature with vapor leads to identical changes in the magnetic characteristics and redistribution of magnetization in its plane.     

Crystallization process and soft magnetic properties of nanocrystalline (Fe0.5 Co0.5 ) 86 Hf7 B6 Cu1 alloy used in elevated temperature applications

Nanocrystalline (Fe0.5 Co0.5 )86 Hf7 B6 Cu1 HITPERM alloy was investigated as the candidate of soft magnetic material for high temperature applications, compared with Fe86 Hf7B6 Cu1 NANOPERM alloy. Amorphous alloy ribbons were prepared by single-roller melt-spinning technology. Crystallization process of as-quenched ribbon was investigated using differential scanning calorimeter at different heating rates. The coercivity was determined from quasi-static hysteresis loop measured at room temperature using a computerized hysteresis loop tracer. X-ray diffraction with Cu Kα radiation was used to determine the structure. The vibrating sample magnetometer was usedto measure the magnetization as a function of temperature of the nanocrystllized alloys. That Co substitution for Fein alloy enhances the Curie temperature of amorphous alloy and the magnetization of nanocrystalline alloy at hightemperature. After annealing amorphous precursor, the optimum nanocrystalline alloy obtained shows the local minimum coercivity. The coercivity increases with the increasing annealing temperature corresponding to the formation of ferromagnetic phase in the secondary crystallization.     

Structural anisotropy of amorphous alloys with creep-induced magnetic anisotropy

Amorphous ribbons of different composition were annealed under tensile stress. This yielded a creep-induced magnetic anisotropy with an easy magnetic plane perpendicular to, or an easy axis parallel to, the ribbon direction, depending on the alloy composition. X-ray diffraction experiments and simple thermal expansion measurements show that the stress-annealed samples reveal a structural anisotropy which is released by post-annealing as a residual strain. This strain increases with the annealing stress and is therefore correlated with the induced magnetic anisotropy. The origin of this frozen-in strain is discussed in terms of structural heterogeneity in the strength of local atomic bonds. It is suggested that the induced magnetic anisotropy is related to the local magneto-elastic coupling in regions with strong bonding forces.     

新型Fe80.5Si7.2B12.3非晶合金带材的退火工艺与磁性能

研究了新型Fe_80.5Si_7.2B_12.3非晶合金带材在不同退火工艺下的磁性能及磁损耗特性,并与传统的铁基非晶合金Fe₈₀Si₉B₁₁进行了对比。结果表明:新型Fe_80.5Si_7.2B_12.3非晶合金带材比Fe₈₀Si₉B₁₁具有更高的饱和磁感应强度,在励磁磁场强度为3500 A/m下其磁通密度值为1.607 T;在f=50 Hz、B_m=1.4 T下,经无磁场退火处理后其磁损耗高于Fe₈₀Si₉B₁₁,达到0.411 W/kg;经纵磁退火后磁损耗与Fe₈₀Si₉B₁₁基本相当,其值为0.197 W/kg;经横磁退火后损耗仅为0.175 W/kg低于Fe₈₀Si₉B₁₁,而且初始磁导率和恒磁导率均优于Fe₈₀Si₉B₁₁;新型Fe_80.5Si_7.2B_12.3非晶合金带材的最佳退火温度区间(360~400 ℃)与Fe₈₀Si₉B₁₁相当。     

Interaction of surface of ribbons of amorphous soft-magnetic iron-based alloys with vapor

The interaction with water vapor of the surface of ribbons of amorphous soft-magnetic iron-based alloys with positive saturation magnetostriction and an effect of the interaction on the magnetization distribution and magnetic properties have been investigated. The results of the investigation showed that, during in-air heat treatment, the interaction of the surface of ribbons of amorphous soft-magnetic alloys with water vapor upon the heating of samples and at the initial stage of isothermal holding exerts a substantial effect on the magnetization distribution and the level of magnetic properties formed. Preliminary room-temperature treatment of the ribbon surface in the as-quenched state with water vapor favors an increase in pseudo-uniaxial tensile stresses along the ribbon axis because, during annealing, the enhanced concentration of hydrogen and oxygen atoms introduced into the ribbon surface is formed in this direction. When certain regimes of heat treatment are used, this leads to an increase in the volume of domains with magnetization oriented along the axis of the ribbon in its plane and allows a significant enhancement in the efficiency of the in-air heat treatment.