The Effect of Annealing on the Formation of Jexaferrite Absorber Coatings Produced by Thermal Spraying Technologies

D. Lisjak, Pertti Lintunen, Tommi Varis, Arto Hujanen, K. Bobzin, K. Richarde, M. Begard, G. Bolelli, L. Lusvarghi, M. Pasquale, E.S. Olivetti, M. Drofenik, T. Schläfer

    Research output: Contribution to conferenceConference articleScientific

    Abstract

    Barium hexaferrites are well-known materials suitable for a variety of applications. In this contribution we present the possibility of applying spraying technologies in the preparation of electromagnetic absorbers based on barium hexaferrites. Thick barium hexaferrite coatings with the compositions BaFel2019 and BaCoTiFelOOl9were deposited by high-velocity oxygen-fuel (HVOF) and atmospheric plasma-spraying (APS) technologies. The coatings were prepared from pre-reacted powders of the desired composition. The crystallization of the hexaferrites was studied by X-ray powder diffractometry, electron microscopy, including microanalysis, which was also combined with thermal analyses and magnetic measurements. The as-deposited coatings were poorly crystallized because of the phase changes induced in the powders "in-flight" in the HVOF and the APS flames and during their quenchingwhile fonning the coating. The coatings produced by APS showed a higher crystallinity than those prepared with HVOF. The largest amount of the hexaferrite phase was obtained in the APS-sprayed BaCoTiFelOOl9coating. In general, the crystallinity of the coatings and their magnetic properties were improved by a subsequent annealing. Fig. I and Table 1 are presented as examples of the annealing studies. Fig. 1 shows the crystallization of the BaCoTiFelOOl9produced by APS followed by annealing. The evolution of the magnetic properties; of the BaFe12019prepared with HVOF depending on the annealing temperatures is presented in Table 1. Similar results were also achieved for the other coatings. Single-phase hexaferrite coatings were obtained at 900°C or at 1000°C, depending on the chemical composition and on the spraying technology. The absorption characteristics were calculated from the electromagnetic properties measured· at 0.4-60 GHz. For tile BaFe12019coatings with thicknesses of 0.15-0.4 mm an enhanced absorption was predicted for mm-waves, while for the BaCoTiFelOOl9coatings with thicknesses of 1-4 mm, enhanced absorption was predicted for microwaves.
    Original languageEnglish
    Publication statusPublished - 2008
    MoE publication typeNot Eligible
    Event10th International Conference on Ferrites ICF10 - Chengdu, China
    Duration: 10 Oct 200813 Oct 2008

    Conference

    Conference10th International Conference on Ferrites ICF10
    Abbreviated titleICF 10
    CountryChina
    CityChengdu
    Period10/10/0813/10/08

    Fingerprint

    spraying
    absorbers
    plasma spraying
    coatings
    annealing
    barium
    oxygen
    crystallinity
    crystallization
    magnetic properties
    electromagnetic properties
    tiles
    microanalysis
    magnetic measurement
    flames
    electron microscopy
    chemical composition
    flight
    electromagnetism
    microwaves

    Cite this

    Lisjak, D., Lintunen, P., Varis, T., Hujanen, A., Bobzin, K., Richarde, K., ... Schläfer, T. (2008). The Effect of Annealing on the Formation of Jexaferrite Absorber Coatings Produced by Thermal Spraying Technologies. Paper presented at 10th International Conference on Ferrites ICF10, Chengdu, China.
    Lisjak, D. ; Lintunen, Pertti ; Varis, Tommi ; Hujanen, Arto ; Bobzin, K. ; Richarde, K. ; Begard, M. ; Bolelli, G. ; Lusvarghi, L. ; Pasquale, M. ; Olivetti, E.S. ; Drofenik, M. ; Schläfer, T. / The Effect of Annealing on the Formation of Jexaferrite Absorber Coatings Produced by Thermal Spraying Technologies. Paper presented at 10th International Conference on Ferrites ICF10, Chengdu, China.
    @conference{a6105eec72d94d6189a3aa638347d007,
    title = "The Effect of Annealing on the Formation of Jexaferrite Absorber Coatings Produced by Thermal Spraying Technologies",
    abstract = "Barium hexaferrites are well-known materials suitable for a variety of applications. In this contribution we present the possibility of applying spraying technologies in the preparation of electromagnetic absorbers based on barium hexaferrites. Thick barium hexaferrite coatings with the compositions BaFel2019 and BaCoTiFelOOl9were deposited by high-velocity oxygen-fuel (HVOF) and atmospheric plasma-spraying (APS) technologies. The coatings were prepared from pre-reacted powders of the desired composition. The crystallization of the hexaferrites was studied by X-ray powder diffractometry, electron microscopy, including microanalysis, which was also combined with thermal analyses and magnetic measurements. The as-deposited coatings were poorly crystallized because of the phase changes induced in the powders {"}in-flight{"} in the HVOF and the APS flames and during their quenchingwhile fonning the coating. The coatings produced by APS showed a higher crystallinity than those prepared with HVOF. The largest amount of the hexaferrite phase was obtained in the APS-sprayed BaCoTiFelOOl9coating. In general, the crystallinity of the coatings and their magnetic properties were improved by a subsequent annealing. Fig. I and Table 1 are presented as examples of the annealing studies. Fig. 1 shows the crystallization of the BaCoTiFelOOl9produced by APS followed by annealing. The evolution of the magnetic properties; of the BaFe12019prepared with HVOF depending on the annealing temperatures is presented in Table 1. Similar results were also achieved for the other coatings. Single-phase hexaferrite coatings were obtained at 900°C or at 1000°C, depending on the chemical composition and on the spraying technology. The absorption characteristics were calculated from the electromagnetic properties measured· at 0.4-60 GHz. For tile BaFe12019coatings with thicknesses of 0.15-0.4 mm an enhanced absorption was predicted for mm-waves, while for the BaCoTiFelOOl9coatings with thicknesses of 1-4 mm, enhanced absorption was predicted for microwaves.",
    author = "D. Lisjak and Pertti Lintunen and Tommi Varis and Arto Hujanen and K. Bobzin and K. Richarde and M. Begard and G. Bolelli and L. Lusvarghi and M. Pasquale and E.S. Olivetti and M. Drofenik and T. Schl{\"a}fer",
    year = "2008",
    language = "English",
    note = "10th International Conference on Ferrites ICF10, ICF 10 ; Conference date: 10-10-2008 Through 13-10-2008",

    }

    Lisjak, D, Lintunen, P, Varis, T, Hujanen, A, Bobzin, K, Richarde, K, Begard, M, Bolelli, G, Lusvarghi, L, Pasquale, M, Olivetti, ES, Drofenik, M & Schläfer, T 2008, 'The Effect of Annealing on the Formation of Jexaferrite Absorber Coatings Produced by Thermal Spraying Technologies', Paper presented at 10th International Conference on Ferrites ICF10, Chengdu, China, 10/10/08 - 13/10/08.

    The Effect of Annealing on the Formation of Jexaferrite Absorber Coatings Produced by Thermal Spraying Technologies. / Lisjak, D.; Lintunen, Pertti; Varis, Tommi; Hujanen, Arto; Bobzin, K.; Richarde, K.; Begard, M.; Bolelli, G.; Lusvarghi, L.; Pasquale, M.; Olivetti, E.S.; Drofenik, M.; Schläfer, T.

    2008. Paper presented at 10th International Conference on Ferrites ICF10, Chengdu, China.

    Research output: Contribution to conferenceConference articleScientific

    TY - CONF

    T1 - The Effect of Annealing on the Formation of Jexaferrite Absorber Coatings Produced by Thermal Spraying Technologies

    AU - Lisjak, D.

    AU - Lintunen, Pertti

    AU - Varis, Tommi

    AU - Hujanen, Arto

    AU - Bobzin, K.

    AU - Richarde, K.

    AU - Begard, M.

    AU - Bolelli, G.

    AU - Lusvarghi, L.

    AU - Pasquale, M.

    AU - Olivetti, E.S.

    AU - Drofenik, M.

    AU - Schläfer, T.

    PY - 2008

    Y1 - 2008

    N2 - Barium hexaferrites are well-known materials suitable for a variety of applications. In this contribution we present the possibility of applying spraying technologies in the preparation of electromagnetic absorbers based on barium hexaferrites. Thick barium hexaferrite coatings with the compositions BaFel2019 and BaCoTiFelOOl9were deposited by high-velocity oxygen-fuel (HVOF) and atmospheric plasma-spraying (APS) technologies. The coatings were prepared from pre-reacted powders of the desired composition. The crystallization of the hexaferrites was studied by X-ray powder diffractometry, electron microscopy, including microanalysis, which was also combined with thermal analyses and magnetic measurements. The as-deposited coatings were poorly crystallized because of the phase changes induced in the powders "in-flight" in the HVOF and the APS flames and during their quenchingwhile fonning the coating. The coatings produced by APS showed a higher crystallinity than those prepared with HVOF. The largest amount of the hexaferrite phase was obtained in the APS-sprayed BaCoTiFelOOl9coating. In general, the crystallinity of the coatings and their magnetic properties were improved by a subsequent annealing. Fig. I and Table 1 are presented as examples of the annealing studies. Fig. 1 shows the crystallization of the BaCoTiFelOOl9produced by APS followed by annealing. The evolution of the magnetic properties; of the BaFe12019prepared with HVOF depending on the annealing temperatures is presented in Table 1. Similar results were also achieved for the other coatings. Single-phase hexaferrite coatings were obtained at 900°C or at 1000°C, depending on the chemical composition and on the spraying technology. The absorption characteristics were calculated from the electromagnetic properties measured· at 0.4-60 GHz. For tile BaFe12019coatings with thicknesses of 0.15-0.4 mm an enhanced absorption was predicted for mm-waves, while for the BaCoTiFelOOl9coatings with thicknesses of 1-4 mm, enhanced absorption was predicted for microwaves.

    AB - Barium hexaferrites are well-known materials suitable for a variety of applications. In this contribution we present the possibility of applying spraying technologies in the preparation of electromagnetic absorbers based on barium hexaferrites. Thick barium hexaferrite coatings with the compositions BaFel2019 and BaCoTiFelOOl9were deposited by high-velocity oxygen-fuel (HVOF) and atmospheric plasma-spraying (APS) technologies. The coatings were prepared from pre-reacted powders of the desired composition. The crystallization of the hexaferrites was studied by X-ray powder diffractometry, electron microscopy, including microanalysis, which was also combined with thermal analyses and magnetic measurements. The as-deposited coatings were poorly crystallized because of the phase changes induced in the powders "in-flight" in the HVOF and the APS flames and during their quenchingwhile fonning the coating. The coatings produced by APS showed a higher crystallinity than those prepared with HVOF. The largest amount of the hexaferrite phase was obtained in the APS-sprayed BaCoTiFelOOl9coating. In general, the crystallinity of the coatings and their magnetic properties were improved by a subsequent annealing. Fig. I and Table 1 are presented as examples of the annealing studies. Fig. 1 shows the crystallization of the BaCoTiFelOOl9produced by APS followed by annealing. The evolution of the magnetic properties; of the BaFe12019prepared with HVOF depending on the annealing temperatures is presented in Table 1. Similar results were also achieved for the other coatings. Single-phase hexaferrite coatings were obtained at 900°C or at 1000°C, depending on the chemical composition and on the spraying technology. The absorption characteristics were calculated from the electromagnetic properties measured· at 0.4-60 GHz. For tile BaFe12019coatings with thicknesses of 0.15-0.4 mm an enhanced absorption was predicted for mm-waves, while for the BaCoTiFelOOl9coatings with thicknesses of 1-4 mm, enhanced absorption was predicted for microwaves.

    M3 - Conference article

    ER -

    Lisjak D, Lintunen P, Varis T, Hujanen A, Bobzin K, Richarde K et al. The Effect of Annealing on the Formation of Jexaferrite Absorber Coatings Produced by Thermal Spraying Technologies. 2008. Paper presented at 10th International Conference on Ferrites ICF10, Chengdu, China.