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1.
 研究了Fe78B13Si9、(Fe0.99Mo0.01)78B13Si9非晶合金的激波晶化行为。激波是由氢-氧爆炸产生的。实验结果表明:激波能使非晶合金在微秒时间内晶化,晶化主相为α-Fe基固溶体,次晶化相为Fe3Si,且观察到α-Fe基因溶体晶格常数变小。用DTA分析进一步证实:激波晶化是比较完全的,晶化相相当稳定。  相似文献   

2.
The crystallization process of the metallic glass Fe28Ni50Si9B13 was investigated by DSC, Hall effect, electrical resistivity, and X-ray diffraction methods. It proceeds in two stages. Ni phase is formed at the temperature of 723 K and Ni3B phase at 773 K. The phase creation is accompanied by an abrupt decrease of the Hall and electrical resistivities and the spontaneous Hall coefficient.  相似文献   

3.
Summary The electrical resistivity of Fe80B20 and Fe78B13Si9 amorphous glasses as a function of temperature from 293 K down to 15 K was measured, and it was found to fit quite well with the model given by Cote and Meisel. Comparison between our resistivity measurements of Fe80B20 and others was made, where some differences were found. These resistivity differences are evidence for a variety of amorphous atomic arrangements of the samples. The longitudinal magnetoresistance of Fe80B20 and Fe78B13Si9 at 293K and 77K was measured in a low magnetic field. The observed magnetoresistance shows a typical field dependence known for ferromagnetic materials.  相似文献   

4.
Effect of thermal neutron irradiation of metallic glasses Fe78Si9B13 and Fe78Si8B14 has been studied using Mossbauer spectroscopy. The surfaces of the two specimens are found to behave very differently under irradiation. The difference may be attributed to the presence of a thin oxide layer at the surface of as-prepared Fe78Si9B13.  相似文献   

5.
The nanocrystallization process of soft ferromagnetic (Fe0.99Mo0.01)78Si9B13 ribbons has been studied in detail. Microstructural and ferromagnetic properties are examined by transmission electron microscopy (TEM), X-ray diffraction (XRD), Mössbauer spectroscopy (MS), differential scanning calorimetry (DSC) and magnetization measurements. The Curie and crystallization temperatures are determined to be TC=665 K and Tx=750 K, respectively. The Tx value is in well agreement with DSC measurement results. XRD patterns had shown two metastable phases (Fe23B6, Fe3B) which were formed under in situ nanocrystallization process. These metastable phases embedded in the amorphous matrix have a significant effect on magnetic ordering. The ultimate nanocrystalline (NC) phases of α-Fe(Mo, Si) and Fe2B at optimum annealing temperature had been observed respectively. It is notable that the magnetization of the amorphous phase decreases more rapidly with increasing temperature than those of NC ferromagnetism, which suggest the presence of the distribution of exchange interaction in the amorphous phase or high metalloid contents.  相似文献   

6.
The influence of compressive stresses on magnetic properties of Co66Fe4Ni1B14Si15 amorphous alloy rings was investigated. In spite of low magnetostriction the stress sensitivity is significant. New method of applying stresses to a ring core is presented.  相似文献   

7.
 在600~930 K,常压到7 GPa的范围内,对非晶(Fe0.99,Mo0.01)78Si9B13合金等温等压退火30 min。实验表明:其晶化产物α-Fe(Mo, Si)、Fe3B和Fe2B相的析出与所加压力密切相关。压力使非晶(Fe0.99,Mo0.01)78Si9B13合金的晶化温度和亚稳Fe3B相的析出温度下降,在一定的压力和温度下,亚稳Fe3B相将向稳定Fe2B相转变,其转变温度随压力而变化。还对非晶(Fe0.99,Mo0.01)78Si9B13合金的晶化和亚稳Fe3B到稳定Fe2B转变的热力学机制进行了讨论,并给出Fe3B向Fe2B的相转变方程。  相似文献   

8.
In the present paper, we report the Meyer-Neldel relation between the pre-exponential factor and activation energy of non-isothermal crystallization of Co66Si16B12Fe4Mo2 metallic glass. Differential scanning calorimeter (DSC) is employed to study the change in the above two kinetic parameters of the crystallization due to ionic irradiation at three different fluences with high-energy heavy ion; Ni11+ of 150 MeV.  相似文献   

9.
The effect of rapid heating on the stability of amorphous Fe45Ni35Si10B10 is studied in detail by Mössbauer spectroscopy. Structural relaxation as well as formation of crystalline α-Fe and γ(FeNi) is observed, depending on the heating and cooling conditions applied.  相似文献   

10.
Linear saturation magnetostrictions (295 K) of Fe80t-xCoxB20, 0?x?80, and Fe80?xNixB20, 0?x?60 (at. %) glasses are reported. The saturation magnetostrictions of the Fe-Ni-base glasses vary as the sqaure of their respective saturation magnetizations. The behavior in the Fe-Co-base glasses is strikingly different. The compositional trends suggest a difference in origin of magnetostrictions between Fe-Ni-base and Co-containing glasses. When magnetostrictions for these glasses are compared with those for Fe-Co and Fe-Ni polycrystalline alloys, the most significant discrepancies appear in the Fe-rich compositions. This is probably related to the difference in short range order between the crystalline and non-crystalline Fe-rich alloys: α-Fe is 8-fold coordinated whereas all of the metallic glasses studied show ~ 12-fold metal coordination.  相似文献   

11.
非晶合金Fe78Si9B13在脉冲电流作用下的单相晶化   总被引:3,自引:0,他引:3       下载免费PDF全文
对非晶合金Fe78Si9B13进行了超短脉冲电流处理,实现了晶化时α-Fe(Si)单相结构析出.可以认为,脉冲电流作用时,电子运动与非晶中空位型结构缺陷间的周期性排斥效应促进了类金属原子从非晶结构单元中析出,使Fe(Si)原子局部富集,导致基体金属相在较低温度下优先成核.而在空位的定向迁移的同时,将伴随B原子的扩散,则B原子局域富集,Fe-B化合物的形核析出就要受到这两个因素的抑制 关键词:  相似文献   

12.
We report microstructure evolution in as-spun Fe78Si9B13 ribbons under various wheel speeds (s), which was investigated by X-ray diffraction (XRD), differential scanning calorimetry (DSC), and transmission electron microscopy (TEM). With decreasing s, the volume fraction of the residual amorphous phase (Va) in the as-spun ribbons decreases gradually, and the total exothermic heat of the crystallization in the DSC curves also decreases, but the ratio of the exothermic heat of the second crystallization to the first one is on the contrary. α-Fe is found in the ribbon with s of 32.9 m/s, while α-Fe, eutectic α-Fe+Fe2B, and Fe3Si phases are found in ribbons with s of 25.6 and 18.3 m/s. The phase precipitating behavior in cooling processes is well consistent with the annealing process in the literatures.  相似文献   

13.
Magnetic parameters, the local anisotropy field Hk, the effective field h related to the correlation radius, and the coercive force Hc, are determined for free and contact surfaces by investigating the magnetization curves of amorphous Fe40Ni40B20 and Fe6Co70Ni13Si7B4 foils by a highly-sensitive method of measuring the magnetooptical phase.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 49–52, November, 1989.  相似文献   

14.
The local environment of Cu atoms in Fe73.5Cu1Nb3Si13.5B9 alloy was investigated by extended X-ray absorption fine structure(EXAFS).Cu clusters began to order when the annealing temperature was around 733 K from the results of the Fourier transform curves.The fitting results showed that the first shell of the near fcc(face-centered cubic)Cu clusters only contained Cu atoms.The coordination number increased with the annealing temperature.Subsequently,the occupancy rate increased from 33.3%(annealed at 733 K)to 100% (annealed at 853 K).This local structural change of Cu atoms could probably affect the distribution of the bcc(body-centered cubic)α-Fe in Fe73.5Cu1Nb3Si13.5B9 alloy.  相似文献   

15.
The influence of structural relaxation caused by long time annealing on magnetic properties of Fe30Ni44Cr4Mo2B15Si5 metallic glasses is investigated by Mössbauer spectroscopy and by magnetization measurements. Remarkable hyperfine field distribution shift to the high field region and increase of the value of exchange constant and Curie temperature are observed after annealing. The observed findings are discussed in terms of the possible annealing induced effects on the local short-range order around the magnetic atoms in investigated samples.  相似文献   

16.
陈岁元  刘常升  李慧莉  崔彤 《物理学报》2005,54(9):4157-4163
在CO2激光功率为50—300W、扫描速度为20mm/s、激光散光斑为20mm照射条件下 ,诱导非 晶Fe735Cu1Nb3Si135B9带中发生结构重组,产生定量纳米α-F e(Si)晶相形成双相组织结构材料. 利用穆斯堡尔谱研究了非晶Fe735C u1Nb3Si135B9合金激光纳米化的 超精细结构. 实验结果表明,激光诱导非晶 Fe735Cu1Nb3Si135B 9纳米化后,其超精细磁场的分布随 着激光功率变 化由单峰向双峰变化,在高功率辐照时, 出现了双峰分布,并且峰位向高场移动. 高激光 功率辐照非晶Fe735Cu1Nb3Si135B9合金纳米晶化相有四种超精细结 构,即2个超精细磁场较小的初晶相和2个超精细磁场较大的纳米晶化相. 其中超精细磁场较 大(17—25MA/m)的α-Fe(Si)相为DO3结构. 关键词: 激光 纳米晶α-Fe(Si) 735Cu1Nb< sub>3Si135B9')" href="#">非晶Fe735Cu1Nb< sub>3Si135B9 超精细结构 超精细磁场  相似文献   

17.
Mössbauer effect and Scanning Electron Microscopy were used to investigate the effect of immersing the amorphous alloy Fe78B13Si9 in 3% NaCl solution over different periods and different pH. The results indicated that the average angle of orientation of the magnetic moments had increased with increasing time of immersion and decrease in pH value. The corrosion product was found to be lepidocrocite (γ-FeOOH).  相似文献   

18.
《Physics letters. A》1988,130(1):52-54
Measurements of mean positron life-times and X-ray diffraction were carried out in unhydrided alloys Fe78Si9B13 of amorphous and crystalline structures, and after hydriding them. The process of hydriding was carried out at a pressure of 55.773 × 105 N/m2. during 168 h. The crystalline samples were obtained after annealing the amorphous alloy Fe78Si9B13 at 673, 773 and 873 K, respectively. The results obtained after the hydriding process suggest thatan additional electron energy band is formed due to introducing hydrogen inside the samples. The annealing process shows that there exists a nonmonotonic relation between the concentration of free electrons and the degree of order to the structure.  相似文献   

19.
The rf collapse and sideband effects are used to study the microstructure of the Fe73.5Cu1Nb3Si13.5B9 alloy in the amorphous and nanocrystalline state. Nanocrystalline grains of -Fe(Si) are formed as a result of annealing of the amorphous alloy at 520–570 °C. The results show that the complete rf collapse of magnetic hfs in the Mössbauer spectra occurs only in the amorphous phase. The rf collapse is strongly affected by the onset of the nanocrystalline phase and is suppressed when the Fe3B and Fe2B phases are formed. Partial collapse allows us to follow the remaining crystalline fractions during the crystalline process. The rf sidebands disappear due to the formation of nanocrystals because of the vanishing magnetostriction.  相似文献   

20.
The present work shows the applicability of Meyer-Neldel relation between the pre-exponential factor and activation energy of non-isothermal crystallization of Fe78B13Si9 metallic glass. Differential scanning calorimeter (DSC) technique is used to observe the variation in the above two kinetic parameters of the non-isothermal crystallization due to ionic irradiation at three different fluences with high-energy heavy ion Ni11+ having energy 150 MeV.  相似文献   

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