Sökning: "Joel Andersson"

Visar resultat 1 - 5 av 15 avhandlingar innehållade orden Joel Andersson.

  1. 1. Modelling of wear and tribofilm growth

    Författare :Joel Andersson; Luleå tekniska universitet; []

    Sammanfattning : Wear is a consequence of nature which becomes costly if uncontrolled. Basic wear protection is provided by lubrication which will decrease the severity of the contact between asperities. LÄS MER

  2. 2. On Invertibility of the Radon Transform and Compressive Sensing

    Författare :Joel Andersson; Jan-Olov Strömberg; Mikko Salo; KTH; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Radon transform; invertibility; compressive sensing; stability estimates; Matematik; Mathematics;

    Sammanfattning : This thesis contains three articles. The first two concern inversion andlocal injectivity of the weighted Radon transform in the plane. The thirdpaper concerns two of the key results from compressive sensing.In Paper A we prove an identity involving three singular double integrals. LÄS MER

  3. 3. Structural evolution of two ore-bearing Palaeoproterozoic metasupracrustal belts in the Kiruna area, Northwestern Fennoscandian Shield

    Författare :Joel Andersson; Tobias Bauer; Olof Martinsson; Luth Stefan; Luleå tekniska universitet; []
    Nyckelord :;

    Sammanfattning : In this project, two key study areas in the northwestern Fennoscandian Shield are under investigation. The “Western supracrustal belt” and “Central Kiruna area” are both located along lithotectonically comparable Rhyacian-Orosirian metasupracrustal belts and both areas are characterized by iron oxide-apatite (IOA) and iron oxide-copper-gold (IOCG)-style mineralizations and related hydrothermal alterations. LÄS MER

  4. 4. Hot Cracking and Grain Boundary Weaknesses of Nickel - Based Superalloys

    Författare :Joel Håkan Andersson; Chalmers University of Technology; []
    Nyckelord :Hot cracks; Notch rupture testing; Eutectic; Weldability; Varestraint testing; Grain boundary weaknesses; Superalloys;

    Sammanfattning : Abstract Grain boundary weaknesses of nickel-based superalloys not only materialize during service in the hot turbine engine sections but also during the weld manufacturing. The performance, in this respect, of the most commonly used alloys at Volvo Aero Corporation (VAC), 718 and the higher temperature capacity Waspaloy, are therefore the main subjects for this thesis. LÄS MER

  5. 5. Weldability of Precipitation Hardening Superalloys – Influence of Microstructure

    Författare :Joel Håkan Andersson; Chalmers University of Technology; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hot cracking; GTAW; Transvarestraint testing; Varestraint testing; Gleeble testing; Solidification cracking; HAZ liquation cracking; Repair welding; Strain age cracking; EBW; DSC thermal analysis;

    Sammanfattning : Superalloys and in particular the precipitation hardened Ni-based superalloys havealways been used extensively in the hot sections of jet engines. Large hot structuralengine components with complex geometry have preferably been cast as single piececomponents since the large scale vacuum investment casting process becameavailable about fifty years ago. LÄS MER