Diode laser beam absorption in laser transformation hardening of low alloy steel

H. Pantsar, Veli Kujanpää

    Research output: Contribution to journalArticleScientificpeer-review

    42 Citations (Scopus)

    Abstract

    Defining and controlling the absorption of the laser beam is important since all of the heating energy is brought to the material through absorption. Even small variations in the absorption change the laser power needed by hundreds of W. In this study the absorption of a diode laser beam to low alloy steel has been measured by a liquid calorimeter and the surface temperature has been measured with a dual wavelength pyrometer. The varied processing parameters were the power intensity of the beam, the interaction time, and the angle between the surface and the optical axis of the laser beam. Surface temperatures during hardening varied from the Ac1 temperature to the melting point. Tests were done with a 3 kW diode laser with a 12×5 mm hardening optic. The absorptivity of a machined clean steel surface ranged from 46% to 72% depending on the processing parameters. Aluminum oxide blasting of the surface increased the relative amount of energy absorbed to the work piece. The coupling rates for blasted surfaces varied from 66% to 81%. Best absorptivity was achieved by applying graphite coating on the surface. Absorptivity values in excess of 85% were measured.
    Original languageEnglish
    Pages (from-to)147 - 153
    Number of pages7
    JournalJournal of Laser Applications
    Volume16
    Issue number3
    DOIs
    Publication statusPublished - 2004
    MoE publication typeA1 Journal article-refereed

    Fingerprint

    high strength steels
    High strength steel
    hardening
    Laser beams
    Hardening
    Semiconductor lasers
    diodes
    laser beams
    Lasers
    absorptivity
    lasers
    surface temperature
    material absorption
    pyrometers
    Pyrometers
    melting points
    calorimeters
    Graphite
    Aluminum Oxide
    Steel

    Cite this

    Pantsar, H. ; Kujanpää, Veli. / Diode laser beam absorption in laser transformation hardening of low alloy steel. In: Journal of Laser Applications. 2004 ; Vol. 16, No. 3. pp. 147 - 153.
    @article{045218f9d7bf4766941d86b36272f0b1,
    title = "Diode laser beam absorption in laser transformation hardening of low alloy steel",
    abstract = "Defining and controlling the absorption of the laser beam is important since all of the heating energy is brought to the material through absorption. Even small variations in the absorption change the laser power needed by hundreds of W. In this study the absorption of a diode laser beam to low alloy steel has been measured by a liquid calorimeter and the surface temperature has been measured with a dual wavelength pyrometer. The varied processing parameters were the power intensity of the beam, the interaction time, and the angle between the surface and the optical axis of the laser beam. Surface temperatures during hardening varied from the Ac1 temperature to the melting point. Tests were done with a 3 kW diode laser with a 12×5 mm hardening optic. The absorptivity of a machined clean steel surface ranged from 46{\%} to 72{\%} depending on the processing parameters. Aluminum oxide blasting of the surface increased the relative amount of energy absorbed to the work piece. The coupling rates for blasted surfaces varied from 66{\%} to 81{\%}. Best absorptivity was achieved by applying graphite coating on the surface. Absorptivity values in excess of 85{\%} were measured.",
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    year = "2004",
    doi = "10.2351/1.1710879",
    language = "English",
    volume = "16",
    pages = "147 -- 153",
    journal = "Journal of Laser Applications",
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    Diode laser beam absorption in laser transformation hardening of low alloy steel. / Pantsar, H.; Kujanpää, Veli.

    In: Journal of Laser Applications, Vol. 16, No. 3, 2004, p. 147 - 153.

    Research output: Contribution to journalArticleScientificpeer-review

    TY - JOUR

    T1 - Diode laser beam absorption in laser transformation hardening of low alloy steel

    AU - Pantsar, H.

    AU - Kujanpää, Veli

    PY - 2004

    Y1 - 2004

    N2 - Defining and controlling the absorption of the laser beam is important since all of the heating energy is brought to the material through absorption. Even small variations in the absorption change the laser power needed by hundreds of W. In this study the absorption of a diode laser beam to low alloy steel has been measured by a liquid calorimeter and the surface temperature has been measured with a dual wavelength pyrometer. The varied processing parameters were the power intensity of the beam, the interaction time, and the angle between the surface and the optical axis of the laser beam. Surface temperatures during hardening varied from the Ac1 temperature to the melting point. Tests were done with a 3 kW diode laser with a 12×5 mm hardening optic. The absorptivity of a machined clean steel surface ranged from 46% to 72% depending on the processing parameters. Aluminum oxide blasting of the surface increased the relative amount of energy absorbed to the work piece. The coupling rates for blasted surfaces varied from 66% to 81%. Best absorptivity was achieved by applying graphite coating on the surface. Absorptivity values in excess of 85% were measured.

    AB - Defining and controlling the absorption of the laser beam is important since all of the heating energy is brought to the material through absorption. Even small variations in the absorption change the laser power needed by hundreds of W. In this study the absorption of a diode laser beam to low alloy steel has been measured by a liquid calorimeter and the surface temperature has been measured with a dual wavelength pyrometer. The varied processing parameters were the power intensity of the beam, the interaction time, and the angle between the surface and the optical axis of the laser beam. Surface temperatures during hardening varied from the Ac1 temperature to the melting point. Tests were done with a 3 kW diode laser with a 12×5 mm hardening optic. The absorptivity of a machined clean steel surface ranged from 46% to 72% depending on the processing parameters. Aluminum oxide blasting of the surface increased the relative amount of energy absorbed to the work piece. The coupling rates for blasted surfaces varied from 66% to 81%. Best absorptivity was achieved by applying graphite coating on the surface. Absorptivity values in excess of 85% were measured.

    U2 - 10.2351/1.1710879

    DO - 10.2351/1.1710879

    M3 - Article

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    SP - 147

    EP - 153

    JO - Journal of Laser Applications

    JF - Journal of Laser Applications

    SN - 1042-346X

    IS - 3

    ER -