Sökning: "laser ablation"

Visar resultat 1 - 5 av 60 avhandlingar innehållade orden laser ablation.

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. Adhesion to machined and laser ablated wood surfaces

   Författare :Micael Stehr; KTH; []
   Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; ablation; adhesion; checks; coating; cracks; excimer laser; gluing; IR laser; mechanical machining; mechanical weak boundary layer; microscopy; notched specimens; pine; planing; sample preparation; sawing; scanning electronmicroscopy; spruce; tip-cracks; UV laser; weak boundary layer; wood;

   Sammanfattning : This thesis is a contribution to the R&D-program ValueActivation at KTH,Division of Wood Technology and Processingand containsfive papers related to the evaluation and development ofmachining techniques (mechanical and irradiation treatments)whereby weak boundaries at the wood surfaces in the form of(mechanical) weak boundary layers and (micro) cracks due tomechanical treatment can be avoided.The first paper describes the development of a method–using a UV laser–to study the mechanically weakenedboundaries. LÄS MER

4. 3. 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

5. 4. By Means of Beams : Laser Patterning and Stability in CIGS Thin Film Photovoltaics

   Författare :Per-Oskar Westin; Marika Edoff; Uwe Zimmermann; Lars Stolt; Friedrich Kessler; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Laser patterning; laser ablation; laser micro-welding; stability; Cu InGa Se2; CIGS; thin film solar cells; thin film photovoltaics; module technology; solar energy; Electronics; Elektronik; Teknisk fysik med inriktning mot elektronik; Engineering Science with specialization in Electronics;

   Sammanfattning : Solar irradiation is a vast and plentiful source of energy. The use of photovoltaic (PV) devices to convert solar energy directly to electrical energy is an elegant way of sustainable power generation which can be distributed or in large PV plants based on the need. LÄS MER

7. 5. Formation of nanoparticles by laser-activated processes

   Författare :Lars Landström; Mats Boman; Peter Heszler; Joop Schoonman; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Inorganic chemistry; nanoparticles; laser-assisted CVD; laser ablation; emission spectroscopy; size-distribution; Oorganisk kemi; Inorganic chemistry; Oorganisk kemi; Inorganic Chemistry; oorganisk kemi;

   Sammanfattning : Due to the small dimensions, nanoparticles and materials consisting of nano-sized building blocks exhibit unique — mostly superior — properties, well differing from their bulk counterpart. Most of the novel properties of nanoparticles (and nanomaterials) are size-dependent, while the majority of the common gasphase methods used for generation of nanopowders result in different, usually wide, size-dispersions. LÄS MER