Magnetic Properties of the Iron–Nickel System: Pressure, Composition, and Grain Size

We present an introduction to FeNi alloys as they appear in nature and how their magnetic properties can be studied in the laboratory. Meteorites provide natural samples which can carry information about our early Solar System and the magnetic fields present at that time. Grain size, and therefore domain state, of magnetic particles is the key to understanding their ability to record magnetic information on geological time scales. Material specific properties can be easier studied and optimized for technological applications from synthetic samples. We present common synthesis methods as well as analytical procedures to analyze the composition, crystal structure, grain size, and magnetic properties of FeNi alloys. We present data compiled from the literature together with our own results from samples synthesized by mechanical alloying and melting. In particular, we demonstrate changes in hysteresis and backfield parameters as well as Curie temperatures linked to composition, pressure, and alloying. The single-domain (SD) threshold in FeNi alloys remains unknown due to methodical limits in grain size and strong magnetic interactions between individual particles.

@incollection{id2337,
  author = {Wack, Michael and Volk, Michael and Wei, Qingguo},
  booktitle = {Magnetic Fields in the Solar System},
  doi = {10.1007/978-3-319-64292-5\_14},
  editor = {L\"uhr, Hermann and Wicht, Johannes and Gilder, Stuart A. and Holschneider, Matthias},
  isbn = {978-3-319-64291-8 978-3-319-64292-5},
  language = {en},
  pages = {383{\textendash}406},
  publisher = {Springer, Cham},
  series = {Astrophysics and Space Science Library},
  title = {Magnetic Properties of the Iron{\textendash}Nickel System: Pressure, Composition, and Grain Size},
  year = {2018},
}

%O Book Section
%A Wack, Michael
%A Volk, Michael
%A Wei, Qingguo
%B Magnetic Fields in the Solar System
%R 10.1007/978-3-319-64292-5_14
%E Lühr, Hermann
%E Wicht, Johannes
%E Gilder, Stuart A.
%E Holschneider, Matthias
%@ 978-3-319-64291-8 978-3-319-64292-5
%G en
%P 383–406
%I Springer, Cham
%S Astrophysics and Space Science Library
%T Magnetic Properties of the Iron–Nickel System: Pressure, Composition, and Grain Size
%D 2018