High power Nd:YAG laser welding in manufacturing of vacuum vessel of fusion reactor

Tommi Jokinen (Corresponding Author), Veli Kujanpää

    Research output: Contribution to journalArticleScientificpeer-review

    29 Citations (Scopus)

    Abstract

    Laser welding has shown many advantages over traditional welding methods in numerous applications. The advantages are mainly based on very precise and powerful heat source of laser light, which change the phenomena of welding process when compared with traditional welding methods. According to the phenomena of the laser welding, penetration is deeper and thus welding speed is higher. Because of the precise power source and high-welding speed, the heat input to the workpiece is small and distortions are reduced. Also, the shape of laser weld is less critical for distortions than traditional welds. For welding thick sections, the usability of lasers is not so practical than with thin sheets, because with power levels of present Nd:YAG lasers depth of penetration is limited up to about 10 mm by single-pass welding. One way to overcome this limitation is to use multi-pass laser welding, in which narrow gap and filler wire is applied. By this process, thick sections can be welded with smaller heat input and then smaller distortions and the process seems to be very effective comparing “traditional” welding methods, not only according to the narrower gap. Another way to increase penetration and fill the groove is by using the so-called hybrid process, in which laser and GMAW (gas metal arc welding) are combined. In this paper, 20-mm thick austenitic stainless steel was welded using narrow gap configuration with a multi-pass technique. Two welding procedures were used: Nd:YAG laser welding with filler wire and with addition of GMAW, the hybrid process. In the welding experiments, it was noticed that both processes are feasible for welding thicker sections with good quality and with minimal distortions. Thus, these processes should be considered when the evaluation of the welding process is done for joining vacuum vessel sectors of ITER.
    Original languageEnglish
    Pages (from-to)349-353
    Number of pages5
    JournalFusion Engineering and Design
    Volume69
    Issue number1-4
    DOIs
    Publication statusPublished - 2003
    MoE publication typeA1 Journal article-refereed

    Fingerprint

    Laser beam welding
    Fusion reactors
    Welding
    Vacuum
    Lasers
    Gas metal arc welding
    Fillers
    Welds
    Wire
    Austenitic stainless steel
    Joining
    Light sources

    Keywords

    • welding

    Cite this

    Jokinen, Tommi ; Kujanpää, Veli. / High power Nd:YAG laser welding in manufacturing of vacuum vessel of fusion reactor. In: Fusion Engineering and Design. 2003 ; Vol. 69, No. 1-4. pp. 349-353.
    @article{55fd1c0dd33c4c13bbb605ead4c0bff2,
    title = "High power Nd:YAG laser welding in manufacturing of vacuum vessel of fusion reactor",
    abstract = "Laser welding has shown many advantages over traditional welding methods in numerous applications. The advantages are mainly based on very precise and powerful heat source of laser light, which change the phenomena of welding process when compared with traditional welding methods. According to the phenomena of the laser welding, penetration is deeper and thus welding speed is higher. Because of the precise power source and high-welding speed, the heat input to the workpiece is small and distortions are reduced. Also, the shape of laser weld is less critical for distortions than traditional welds. For welding thick sections, the usability of lasers is not so practical than with thin sheets, because with power levels of present Nd:YAG lasers depth of penetration is limited up to about 10 mm by single-pass welding. One way to overcome this limitation is to use multi-pass laser welding, in which narrow gap and filler wire is applied. By this process, thick sections can be welded with smaller heat input and then smaller distortions and the process seems to be very effective comparing “traditional” welding methods, not only according to the narrower gap. Another way to increase penetration and fill the groove is by using the so-called hybrid process, in which laser and GMAW (gas metal arc welding) are combined. In this paper, 20-mm thick austenitic stainless steel was welded using narrow gap configuration with a multi-pass technique. Two welding procedures were used: Nd:YAG laser welding with filler wire and with addition of GMAW, the hybrid process. In the welding experiments, it was noticed that both processes are feasible for welding thicker sections with good quality and with minimal distortions. Thus, these processes should be considered when the evaluation of the welding process is done for joining vacuum vessel sectors of ITER.",
    keywords = "welding",
    author = "Tommi Jokinen and Veli Kujanp{\"a}{\"a}",
    year = "2003",
    doi = "10.1016/S0920-3796(03)00071-1",
    language = "English",
    volume = "69",
    pages = "349--353",
    journal = "Fusion Engineering and Design",
    issn = "0920-3796",
    publisher = "Elsevier",
    number = "1-4",

    }

    High power Nd:YAG laser welding in manufacturing of vacuum vessel of fusion reactor. / Jokinen, Tommi (Corresponding Author); Kujanpää, Veli.

    In: Fusion Engineering and Design, Vol. 69, No. 1-4, 2003, p. 349-353.

    Research output: Contribution to journalArticleScientificpeer-review

    TY - JOUR

    T1 - High power Nd:YAG laser welding in manufacturing of vacuum vessel of fusion reactor

    AU - Jokinen, Tommi

    AU - Kujanpää, Veli

    PY - 2003

    Y1 - 2003

    N2 - Laser welding has shown many advantages over traditional welding methods in numerous applications. The advantages are mainly based on very precise and powerful heat source of laser light, which change the phenomena of welding process when compared with traditional welding methods. According to the phenomena of the laser welding, penetration is deeper and thus welding speed is higher. Because of the precise power source and high-welding speed, the heat input to the workpiece is small and distortions are reduced. Also, the shape of laser weld is less critical for distortions than traditional welds. For welding thick sections, the usability of lasers is not so practical than with thin sheets, because with power levels of present Nd:YAG lasers depth of penetration is limited up to about 10 mm by single-pass welding. One way to overcome this limitation is to use multi-pass laser welding, in which narrow gap and filler wire is applied. By this process, thick sections can be welded with smaller heat input and then smaller distortions and the process seems to be very effective comparing “traditional” welding methods, not only according to the narrower gap. Another way to increase penetration and fill the groove is by using the so-called hybrid process, in which laser and GMAW (gas metal arc welding) are combined. In this paper, 20-mm thick austenitic stainless steel was welded using narrow gap configuration with a multi-pass technique. Two welding procedures were used: Nd:YAG laser welding with filler wire and with addition of GMAW, the hybrid process. In the welding experiments, it was noticed that both processes are feasible for welding thicker sections with good quality and with minimal distortions. Thus, these processes should be considered when the evaluation of the welding process is done for joining vacuum vessel sectors of ITER.

    AB - Laser welding has shown many advantages over traditional welding methods in numerous applications. The advantages are mainly based on very precise and powerful heat source of laser light, which change the phenomena of welding process when compared with traditional welding methods. According to the phenomena of the laser welding, penetration is deeper and thus welding speed is higher. Because of the precise power source and high-welding speed, the heat input to the workpiece is small and distortions are reduced. Also, the shape of laser weld is less critical for distortions than traditional welds. For welding thick sections, the usability of lasers is not so practical than with thin sheets, because with power levels of present Nd:YAG lasers depth of penetration is limited up to about 10 mm by single-pass welding. One way to overcome this limitation is to use multi-pass laser welding, in which narrow gap and filler wire is applied. By this process, thick sections can be welded with smaller heat input and then smaller distortions and the process seems to be very effective comparing “traditional” welding methods, not only according to the narrower gap. Another way to increase penetration and fill the groove is by using the so-called hybrid process, in which laser and GMAW (gas metal arc welding) are combined. In this paper, 20-mm thick austenitic stainless steel was welded using narrow gap configuration with a multi-pass technique. Two welding procedures were used: Nd:YAG laser welding with filler wire and with addition of GMAW, the hybrid process. In the welding experiments, it was noticed that both processes are feasible for welding thicker sections with good quality and with minimal distortions. Thus, these processes should be considered when the evaluation of the welding process is done for joining vacuum vessel sectors of ITER.

    KW - welding

    U2 - 10.1016/S0920-3796(03)00071-1

    DO - 10.1016/S0920-3796(03)00071-1

    M3 - Article

    VL - 69

    SP - 349

    EP - 353

    JO - Fusion Engineering and Design

    JF - Fusion Engineering and Design

    SN - 0920-3796

    IS - 1-4

    ER -