Sökning: "Paul Åkerström"

Visar resultat 1 - 5 av 9 avhandlingar innehållade orden Paul Åkerström.

  1. 1. Material characterisation for simulation of press hardening

    Författare :Paul Åkerström; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hållfasthetslära; Solid Mechanics;

    Sammanfattning : The growing effort to reduce vehicle weight and improve passive safety in the automotive industry has drastically increased the demand for ultra high strength steel components. There exist several production methods for such components, where the press hardening technique (hot stamping) is one of the most successful in producing complex components from boron steel. LÄS MER

  3. 2. Modelling and simulation of hot stamping

    Författare :Paul Åkerström; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hållfasthetslära; Solid Mechanics;

    Sammanfattning : The growing effort to reduce vehicle weight and improve passive safety in the automotive industry has drastically increased the demand for ultra high strength steel components. There are several production technologies for such components. LÄS MER

  4. 3. Material characterization of AA7075-T651 deformed at different temperatures and strain rates

    Författare :Biswajit Dalai; Lars-Erik Lindgren; Paul Åkerström; Marta-Lena Antti; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hållfasthetslära; Solid Mechanics;

    Sammanfattning : In this licentiate thesis, the mechanical response and the microstructure evolution in aluminum alloy (AA) 7075 in its T651 heat treated state have been studied through mechanical tests at varied conditions of strain rate and temperature.First, compression tests were performed on AA7075-T651 samples at room temperature (RT), 100, 200, 300, 400 and 500 °C (melting temperature of AA7075 is ~635 °C) with two comparatively low strain rates of 0. LÄS MER

  5. 4. Modeling and Simulation of Weld Hot Cracking

    Författare :Joar Draxler; Lars-Erik Lindgren; Jonas Edberg; Paul Åkerström; Jesper Hattel; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Material Mechanics; Materialmekanik;

    Sammanfattning : Several alloy systems are susceptible to weld hot cracking. Weld hot cracking occurs by fracture of liquid films, normally grain boundary liquid films, at the late stage of the solidification of the weld. The cracks can be small and therefore difficult to detect by nondestructive test methods. LÄS MER

  7. 5. Effect of Stress Relief Annealing: Part Distortion, Mechanical Properties, and Microstructure of Additively Manufactured Austenitic Stainless Steel

    Författare :Emil Edin; Marta-Lena Antti; Pia Åkerfeldt; Fredrik Svahn; Magnus Neikter; Paul Åkerström; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Laser powder bed fusion; stainless steel; residual stress; heat treatment; tensile testing; relaxation testing; Materialteknik; Engineering Materials;

    Sammanfattning : Additive manufacturing (AM) processes may introduce large residual stresses in the as-built part, in particular the laser powder bed fusion process (L-PBF). The residual stress state is an inherent consequence of the heterogeneous heating and subsequent cooling during the process. LÄS MER