Skip to Main content Skip to Navigation
Theses

Elaboration et étude de poudres magnétiques douces (Ni-Fe, Ni-Fe-X, Ni-Fe-X-Y) à l'état nanocristallin par broyage mécanique de haute énergie

Abstract : The Ni3Fe intermetallic compound and the 79Ni16Fe5Mo and 77Ni14Fe5Cu4Mo (wt. %) alloys have been obtained by high energy mechanical milling. For the given conditions, the minimum time needed for theirs formation has been established. The alloys formation has been followed by X-ray and neutron diffraction and thermomagnetic analyses. For the Ni3Fe intermetallic compound the annealing effect on his formation has been proved; the annealing temperatures were 400 °C and 450 °C. The recrystallization temperature and formation enthalpy of Ni3Fe have been obtained by differential scanning calorimetry. The coercitive field evolution with milling time and crystallite size is also discussed. A formation mechanism of the Ni-Fe alloys under the temperature and magnetic field is proposed. A extended milling – annealing – transformation diagram for the Ni3Fe formation is given. For the NiFeMo alloy, the magnetisation evolution with the milling time is showed; also the reproductibility of magnetic properties for different alloys series is discussed. The sensibility of neutron diffraction has been used to show the iron contamination by the containers and/or balls for the long milling times. For the NiFeCuMo alloy, the spontaneous magnetisation evolution with the milling time is analyzed. The long time milling influence to the alloy composition is showed. For the long milling times, a difference between the Curie temperature at heating and cooling is observed and discussed.
Document type :
Theses
Complete list of metadatas

Cited literature [215 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-00258428
Contributor : Florin Popa <>
Submitted on : Friday, February 22, 2008 - 10:19:45 AM
Last modification on : Thursday, November 19, 2020 - 1:00:54 PM
Long-term archiving on: : Thursday, May 20, 2010 - 7:27:17 PM

Identifiers

  • HAL Id : tel-00258428, version 1

Collections

CNRS | NEEL | UJF | UGA

Citation

Florin Popa. Elaboration et étude de poudres magnétiques douces (Ni-Fe, Ni-Fe-X, Ni-Fe-X-Y) à l'état nanocristallin par broyage mécanique de haute énergie. Matière Condensée [cond-mat]. Université Joseph-Fourier - Grenoble I, 2008. Français. ⟨tel-00258428⟩

Share

Metrics

Record views

641

Files downloads

5461