Sökning: "Laser Beam"

Visar resultat 1 - 5 av 299 avhandlingar innehållade orden Laser Beam.

  1. 1. Pulsed laser ablation studied using digital holography

    Författare :Eynas Amer; Bill O’Neill; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Experimental Mechanics; Experimentell mekanik;

    Sammanfattning : Pulsed digital holographic interferometry has been used to study the plume and the shock wave generated in the laser ablation process on different targets under atmospheric air pressure. A pulsed Nd-YAG laser system (pulse duration 12 ns) has been used both for ablating the material (wavelength 1064 nm) and for measurement (wavelength 532 nm). LÄS MER

  3. 2. Laser cutting and piercing: Experimental and theoretical investigation

    Författare :Jetro Pocorni; Alexander F. H. Kaplan; John Powell; Jan Frostevarg; William O'Neill; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Laser cutting; laser piercing; efficiency; fibre laser; CO2 laser; high speed imaging; Produktionsutveckling; Manufacturing Systems Engineering; Maskinteknik;

    Sammanfattning : This thesis concerns experimental investigations of laser cutting and piercing, with theoretical and practical discussions of the results. The thesis is made up of an introduction to laser cutting and six scientific Papers. LÄS MER

  4. 3. Novel beam shaping and computer vision methods for laser beam welding

    Författare :Yongcui Mi; Antonio Ancona; Fredrik Sikström; Isabelle Choquet; Högskolan Väst; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Laser beam welding; Beam shaping; Deformable mirror; Process monitoring; Process control; Model validation; Computer vision; Machine learning; Butt joint; T-joint.; Lasersvetsning; Beam shaping; Deformerbar spegel; Processövervakning; Processkontroll; Modellvalidering; Datorsyn; Maskininlärning; Butt joint; T-fogar;

    Sammanfattning : Laser beam welding has been widely applied in different industrial sectors due to its unique advantages. However, there are still challenges, such as beam positioning in T-joint welding, and gap bridging in butt joint welding,especially in the case of varying gap width along a joint. LÄS MER

  5. 4. Hyperfine structure, isotope shifts and transition probabilities in singly charged atoms : laser - ion beam studies

    Författare :Petrine Villemoes; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP;

    Sammanfattning : .... LÄS MER

  7. 5. Spectral analysis in laser powder bed fusion

    Författare :Benedikt Brandau; Frank Brückner; Alexander Kaplan; Dan Roth-Fagaraseanu; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Spectral monitoring; Laser powder bed fusion; Laser optics; Absorbance; Produktionsutveckling; Manufacturing Systems Engineering;

    Sammanfattning : This thesis is about the investigation of the spectral interaction of electromagnetic radiation with metal powders. For this purpose, spectral data of powders for laser powder bed fusion processes are investigated in three papers using different techniques. LÄS MER