Sökning: "Fe-Ni alloys"

Visar resultat 1 - 5 av 17 avhandlingar innehållade orden Fe-Ni alloys.

  1. 1. Mössbauer Spectroscopy of Meteoritic and Synthetic Fe-Ni Alloys

    Författare :Yassir Ahmed Mohamed Abdu; Hans Annersten; Tore Ericsson; Johan Linden; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; Earth sciences; Meteorites; Tetrataenite; Antitaenite; Mössbauer spectroscopy; Mechanical alloying; Fe-Ni alloys; High pressure; Geovetenskap; Earth sciences; Geovetenskap; mineralogi; petrologi och tektonik; Mineral Chemistry; Petrology and Tectonics;

    Sammanfattning : This thesis reports on the results of investigating Fe-containing minerals in meteorites, with focus on Fe-Ni minerals and their magnetic properties, along with some synthetic Fe-Ni analogues. The New Halfa meteorite, which fell in Sudan 1994, has been studied using Mössbauer spectroscopy, X-ray diffraction, and electron microprobe analysis techniques, and classified as an ordinary L-type chondrite of petrologic type 4. LÄS MER

  2. 2. Characterization and Modification of Microstructure in Al-Co-Cr-Fe-Ni Eutectic High-Entropy Alloys

    Författare :Adrianna Lozinko; Chalmers University of Technology; []
    Nyckelord :eutectic alloys; solidification; orientation relationship; high-entropy alloys; microstructure; EBSD; recrystallization;

    Sammanfattning : The recently emerging high-entropy alloys (HEAs) present a novel alloying strategy, significantly expanding the scope of metal alloy design. HEAs are defined as alloys consisting of at least four principal elements in equi- or near equiatomic ratios, with a possibility of small amounts of alloying elements. LÄS MER

  3. 3. First-principles study of spin-flip transition in Fe-Ni invar alloys

    Författare :François Liot; Linköpings universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP;

    Sammanfattning : More than a hundred years ago, Guillaume discovered that the alloy Fe65Ni35, at equilibrium under normal pressure, was invar. Indeed, its thermal expansion coefficient was anomalously small over a wide temperature interval. It is now known that the invar effect in this alloy is related to magnetism. LÄS MER

  4. 4. Ab initio prediction of the mechanical properties of alloys

    Författare :Guisheng Wang; Levente Vitos; Qing-Miao Hu; Douglas Irving; KTH; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Industriell ekonomi och organisation; Industrial Engineering and Management;

    Sammanfattning : At the time of the 50th anniversary of the Kohn-Sham method, ab initio calculations based on density functional theory have formed an accurate, efficient, and reliable method to work on the properties of engineering materials. In this thesis, we use the exact muffin-tin orbitals method combined with the coherent-potential approximation to study the mechanical properties of high-technology materials. LÄS MER

  5. 5. Metallic Amorphous Thin Films and Heterostructures with Tunable Magnetic Properties

    Författare :Atieh Zamani; Petra Jönsson; Olof Karis; Per Nordblad; Yves Idzerda; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Amorphous; Thin Film; Magnetic properties; FeZr alloys; Ion implantation; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : The primary focus of this thesis is to study the effect of doping on magnetic properties in amorphous Fe100−xZrx alloys. Samples with compositions of x = 7,11.6 and 12 at.% were implanted with different concentrations of H. LÄS MER