Development of novel permanent magnets

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Project abstract

This project aims to further investigate the appropriateness of the promising rare-earth free permanent magnet materials such as MnAl based alloys as a permanent magnet material. The transition to the desired ferromagnetic L10 phase has been previously improved by the addition of ~2 at.% Carbon. Mainly in this project the optimization (related to Hailiang Fang’s PhD project) of the magnetic properties has been done through different processing routes of the MnAlC powder produced both in-house and in collaboration with Höganäs AB. Microstructural characterization (size, shape, crystal orientation) is done by electron microscopy and light optical microscopy in collaboration with Höganäs AB. The Magnetic properties are measured in collaboration with Prof. Peter Svedlindh’s group.

Related to new alloys, FeNi known as the “meteorite phase” or tetrataenite that is formed <320C and takes 1 000 000 000+ years to form due to the low mobility of the atoms. The L10 phase of the FeNi has the potential to compete with rare-earth permanent magnets when comparing the BHmax values. The samples are made with addition of extra elements to study if any possibility exists to stabilize the L10 phase in “realistic” time scales in bulk. Samples are made in-house by arc-melting followed by heat treatments in vacuum. Magnetic properties screening is done by Peter Svedlindh’s group.

Summary of work

The work related to the SEWGRID project started with studies of different heat treatments of MnAl based powders from Höganäs AB to identify temperature regions for improved tau phase purity and magnetic properties. The work was complemented at Höganäs AB and resulted in a patent application together with the cryomilling process studied by Hailiang Fang. During the second half of the spring, we started a comparison study of MnAl synthesized by two different routes. One of the routes improved the phase purity, microstructure and magnetic properties significantly and is now currently being summarized into a manuscript. In parallel, studies with additional dopants is pursued during the second half of the year in order to find elements that can enhance the coercivity significantly for the optimized MnAlC composition, without deteriorating the maximum attainable magnetization for the sample.

Moreover, samples made in the FeNi system, in an attempt to find a way to synthesize the ordered L10 phase was also attempted. So far, pieces annealed at different time lengths at 300C did not result in a significant enhancement of the coercivity in the FeNi alloy. Indicating that the soft magnetic phase is the main phase still.

As of end of 2017, the focus will be to finish the manuscript that is being prepared and to finish the synthesis of MnAlC with additional dopants.

Event log

2017. Successful identification of temperature ranges and compositions for the conversion of MnAlC from the epsilon phase to the tau phase

2017. The cryomilling procedure in combination with heat treatment is prepared for a patent application by Höganäs AB

2017. A manuscript on the cryomilling related to (Hailiang Fang’s PhD project) is prepared and submitted for publication: "Structural, microstructural and magnetic evolution in cryo milled carbon doped MnAl".

2017. Received poster prize 2nd place at SweGRIDS conference.

Project reference-group

Dr Per-Olof Larsson,  Höganäs AB
Dr Hilmar Vidarsson,  Höganäs AB
Dr Björn Skårman,  Höganäs AB
Dr Klas Gunnarsson,  UU
Professor Peter Svedlindh,  UU

Publications by this researcher

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Phase stability and structural transitions in compositionally complex LnMO(3) perovskites
Johan Cedervall,   Rebecca Clulow,   Hanna Boström,   Deep C. Joshi,   Mikael Andersson,   Roland Mathieu,   Premysl Beran,   I Smith, Ronald,   Jo-Chi Tseng,   Martin Sahlberg,   Pedro Berastegui,   Samrand Shafeie.
2021,   Journal of Solid State Chemistry, vol. 300

Measured and calculated properties of B-doped τ-phase MnAl : A rare earth free permanent magnet
Sofia Kontos,   Hailiang Fang,   Jiheng Li,   Erna Krisztina Delczeg-Czirjak,   Samrand Shafeie,   Peter Svedlindh,   Martin Sahlberg,   Klas Gunnarsson.
2019,   Journal of Magnetism and Magnetic Materials, vol. 474

Cation ordering, ferrimagnetism and ferroelectric relaxor behavior in Pb(Fe1-xScx)(2/3)W1/3O3 solid solutions
Sergey Ivanov,   Premysl Beran,   Alexandr A. Bush,   Tapati Sarkar,   Samrand Shafeie,   Duo Wang,   Biplab Sanyal,   Olle Eriksson,   Martin Sahlberg,   Yaroslav Kvashnin,   Roland Tellgren,   Per Nordblad,   Roland Mathieu.
2019,   European Physical Journal B: Condensed Matter Physics, vol. 92(8)

One step towards MnAl-based permanent magnets : Differences in magnetic, and microstructural properties from an intermediate annealing step during synthesis
Samrand Shafeie,   Hailiang Fang,   Daniel Hedlund,   Axel Nyberg,   Peter Svedlindh,   Klas Gunnarsson,   Martin Sahlberg.
2019,   Journal of Solid State Chemistry, vol. 274

Insights into phase transitions and magnetism of MnBi crystals synthesized from self-flux
Hailiang Fang,   Jiheng Li,   Samrand Shafeie,   Daniel Hedlund,   Johan Cedervall,   Fredrik Ekström,   Cesar Pay Gómez,   Jozef Bednarcik,   Peter Svedlindh,   Klas Gunnarsson,   Martin Sahlberg.
2019,   Journal of Alloys and Compounds, vol. 781

Synthesis, X-ray Diffraction Characterization, Mössbauer Spectroscopy, and Dielectric Properties of Solid Solutions in the PbFe_2/3W_1/3O₃–PbSc_2/3W_1/3O₃ System
A. F. Koroleva,   A. A. Bush,   K. E. Kamentsev,   V. Ya. Shkuratov,   Sergey Ivanov,   V. M. Cherepanov,   Samrand Shafeie.
2018,   Inorganic Materials (Neorganicheskie materialy), vol. 54(3)

Accelerated oxidation in ductile refractory high-entropy alloys
Saad Sheikh,   Muhammad Kurnia Bijaksana,   Amir Motallebzadeh,   Samrand Shafeie,   Adrianna Lozinko,   Lu Gan,   Te-Kang Tsao,   Uta Klement,   Demircan Canadinc,   Hideyuki Murakami,   Sheng Guo.
2018,   Intermetallics (Barking), vol. 97

Aluminizing for enhanced oxidation resistance of ductile refractory high-entropy alloys
Saad Sheikh,   Lu Gan,   Te-Kang Tsao,   Hideyuki Murakami,   Samrand Shafeie,   Sheng Guo.
2018,   Intermetallics (Barking), vol. 103

Structural, microstructural and magnetic evolution in cryo milled carbon doped MnAl
Hailiang Fang,   Johan Cedervall,   Daniel Hedlund,   Samrand Shafeie,   Stefano Deledda,   Fredrik Olsson,   Linus von Fieandt,   Jozef Bednarcik,   Peter Svedlindh,   Klas Gunnarsson,   Martin Sahlberg.
2018,   Scientific Reports, vol. 8(1)

Publication list last updated from DiVA on 2024-01-10 15:22.

Page started: 2017-01-01
Last generated: 2024-01-10