Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Magnetovolume effects and magnetic anisotropy in Ce3(FeM)29 compounds (M=Ti, Cr) (1995)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 78 (1995), S. 4615-4620 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The magnetovolume effects and magnetic anisotropy of the new Ce3(FeTi)29 and Ce3(FeCr)29 compounds have been studied by measuring their linear thermal expansion (LTE), pressure dependence of the Curie temperature Tc, compressibility, and anisotropy field. The value of Tc, its pressure dependence dTc/dp, and anisotropy field HA for the Ce(FeCr)12 phase are also reported. The linear thermal expansion of these compounds exhibits Invar-like behavior with large positive values of the spontaneous magnetostriction at Tc [e.g., ωs(0)≈1.2% in Ce3(FeTi)29]. Different values of the compressibility have been observed in the ferromagnetic and paramagnetic states of Ce3(FeTi)29 (κf=1.25×10−3 kbar−1 and κp=1.12×10−3 kbar−1) in qualitative agreement with the large magnetovolume effect observed in the LTE. Tc for all the phases studied decreases under pressure with initial slopes dTc/dp=−3.75, −3.6, and −2.7 K/kbar for Ce3(FeTi)29, Ce3(FeCr)29, and Ce(FeCr)12, respectively. Two anisotropy fields have been detected in Ce3(FeTi)29 associated with saturation along the b (HA) and c (H′A) axes of the monoclinic structure. The temperature dependence of H′A for Ce3(FeCr)29 and HA for Ce(FeCr)12 is also reported. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.359807
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Magnetocrystalline anisotropy of the 3d sublattice in the cubic intermetallic system Zr6Co23−xMx (M=Fe,Ni) (1993)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 73 (1993), S. 2941-2947 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The magnetocrystalline anisotropy behavior of the 3d sublattice was studied in the face-centered-cubic system Zr6Co23−xMx (M=Fe,Ni). A remarkably high anisotropy field was required to saturate the magnetization along both the [100] and [110] hard directions. The values found are, respectively, HA=43 kOe and HA=33 kOe at 293 K for Zr6Co23. The partial substitution of Co with Ni results in a substantial increase of the anisotropy while saturation magnetization and Curie temperature decrease linearly. On the contrary, the partial substitution with Fe gives rise to a decrease of HA and to an increase of both σs and Tc. The 10th power law does not apply to the functional temperature dependence of the resulting anisotropy in this system.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.353025
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Magnetic anisotropy and magnetization processes in 3:29 and 1:12 Nd(FeTi)-based compounds (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 76 (1994), S. 7473-7477 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The temperature behavior of the magnetic anisotropy and magnetization processes in the tetragonal Nd(FeTi)12 and monoclinic Nd3(FeTi)29 have been studied and compared. Both compounds are characterized by the occurrence of temperature-induced spin reorientation transitions, as well as field-induced magnetization processes of different types, which have been interpreted as first-order magnetization process. In both systems the resultant anisotropy of Nd favors the occurrence of an easy magnetization direction out of the principal axes at low temperature. On the contrary the overall Fe sublattice anisotropy favors the tetragonal c-axis in the 1:12 and seems to prefer the monoclinic a-axis in the 3:29 compound. © 1994 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.357976
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Simple and direct method to determine the single or polydomain status of the particles in a uniaxial ferromagnetic polycrystal: Measure of the coercive and anisotropy fields (1988)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 59 (1988), S. 1215-1218 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: We present a method and the corresponding apparatus which allow one to determine the single or polydomain status of the particles in a uniaxial ferromagnetic polycrystal. The method is based on the measurement of the field dependence of the transverse susceptibility χt(H). The proposed technique also allows for the measure of the coercive field of the specimen. Furthermore, the anisotropy field can be measured for the single-domain particle samples.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1139699
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Magnetic, Mössbauer, and neutron diffraction investigations of W-type hexaferrite BaZn2−xCoxFe16O27 single crystals (1988)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 63 (1988), S. 5074-5080 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Macroscopic magnetic measurements, Mössbauer, and neutron diffraction studies have been carried out on BaCoxZn2−xFe16O27 [(Zn−Co)2-W] single-crystal hexaferrites. The extrapolated saturation magnetization values σs(0) are slightly lower than those found in the literature. Such differences have been justified as due to the different Co and Zn distributions among the tetrahedral sites.The Co ions induce a strong planar contribution to the magnetic anisotropy. At low temperature, the spin order, found from the macroscopic magnetic measurements and preliminary neutron diffraction studies, is planar, while the Mössbauer data indicate a conical order with an angle of 70° with respect to the c axis. By increasing the temperature, the cobalt anisotropy decreases and a spin reorientation to easy axis is observed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.340405
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Magnetic investigation of a (Co,Zn)2 W-type hexaferrite (abstract) (1987)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 61 (1987), S. 3301-3301 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Single-crystal samples of cobalt-zinc W-type hexagonal oxides were flux grown and magnetically investigated over the temperature range 78–700 K. As it is well known cobalt has a large influence on the magnetocrytalline anisotropy of ferromagnetic oxides. With varying the Co concentration and the temperature, the easy direction of magnetization in this system changes from the basal plane to an easy and/or to an easy cone undergoing different spin reorientation transitions. In some cases one also observes first-order magnetization processes (FOMP).1 We will present the magnetic phase diagram of the system CoxZn2−x-W, 0≤x≤2, and the analysis of the magnetization curves, measured for different samples at various temperatures in terms of anisotropy constants up to the sixth order, in the usual power expansion for the anisotropy energy. Also the dependence on the composition of the Curie temperature and saturation magnetization will be reported. The results will be analyzed on the basis of a simple model2 which takes into account the competition between different sublattices anisotropies and exchange.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.338889
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Competing anisotropies and first-order magnetization processes in (Zn,Co)W-type hexaferrite (1986)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 60 (1986), S. 3680-3684 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: First-order magnetization processes (FOMP) and spin reorientation phase transitions are known to occur in hexaferrites as well as in rare-earth transition-metal compounds. This complex phenomenology has been described using high-order terms in the anisotropy energy expansion. In order to understand the microscopic origin of these high-order anisotropy constants in hexaferrites we have made a detailed analysis of the magnetic properties of BaZn1.1Co0.9Fe16O27 which shows, at the same temperature, easy cone anisotropy and a FOMP. We have found good agreement between the experimental data and the predictions of a simple two sublattice model which takes into account the effect of the competition between the exchange and the difference in the anisotropy of the sublattices. This strongly supports the hypothesis that such a competition and the subsequent noncollinear order are the origin of the observed large high-order anisotropy constants in hexaferrites as in intermetallic compounds.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.337575
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Surface doping with Al in Ba-hexaferrite powders (abstract) : 35th annual conference on magnetism and magnetic materials (1991)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 69 (1991), S. 5535-5535 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Barium M-hexaferrites were intensively studied in order to improve their magnetic characteristics for application as permanent magnets using different ion substitutions. However, substitutions that improve the BHmax energy product have not been found. We propose a new method in order to modify the extrinsic magnetic characteristics of Ba-hexaferrite powders without reducing drastically the magnetization and the magnetic anisotropy. This method consists in the surface doping of the hexaferrite particles, giving as a result a modification of the energy pinning of the domain walls at the grain boundary. Ba ferrite powders having a mean diameter of 3.2 μm have been dry mixed with Al2O3 powders with a diameter 〈0.5 μm. From the mixed powder a series of 10 cylindrically shaped samples was obtained by isostatically pressing the powders. The samples were thermically treated from 900 to 1200 °C, together with 10 cylindrical samples of pure hexaferrite, for 1 h each. For all the samples we have measured the Curie temperature (Tc), the anisotropy field (HA), the coercive field (Hc), and the saturation magnetization σ. The main results are that up to 1000 °C the Al diffusion is mainly localized at the surface of the grain so that the main part of the grain is undoped as confirmed by the Tc and HA values that are the same as those found in pure hexaferrites. From 900 to 1000 °C the saturation magnetization decreases of the 3% while Hc increases of the 9% with respect to the pure hexaferrite. This result seems to confirm the validity of the proposed method. Above 1000 °C Al begin to diffuse in the grain and above 1200 °C it is possible to say, from thermomagnetic analysis, that Al has diffused uniformly throughout the grain. In this last temperature range the Al substitution leads to a 10% reduction in σ as expected1 while Hc only increases 12%. These preliminary results suggest that the method of surface doping of the powders could be used in order to increase or decrease the H〈INF〉 values without strongly influencing the σ values.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.347967
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Influence of the particle size and intrinsic magnetic characteristics on the coercivity of sintered magnets
    Amsterdam : Elsevier
    Journal of Magnetism and Magnetic Materials 104-107 (1992), S. 1143-1144 
    Details
    ISSN: 0304-8853
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1016/0304-8853(92)90524-R
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Comparative measurements of the effective anisotropy field H"a for barium ferrites
    Amsterdam : Elsevier
    Journal of Magnetism and Magnetic Materials 114 (1992), S. 193-201 
    Details
    ISSN: 0304-8853
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0304-8853(92)90344-N
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...