Sökning: "Jörgen Kajberg"

Visar resultat 1 - 5 av 13 avhandlingar innehållade orden Jörgen Kajberg.

  1. 1. Displacement field measurement using digital speckle photography for characterisation of materials subjected to large deformations and high strain rates

    Författare :Jörgen Kajberg; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hållfasthetslära; Solid Mechanics;

    Sammanfattning : In many technical processes, material is deformed under conditions involving large deformations (strains) and/or high strain rates. Examples of such processes are collisions, impact, penetration, metal forming, powder compaction and crack propagation. LÄS MER

  3. 2. High strain-rate experiments using high-speed photography

    Författare :Jörgen Kajberg; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hållfasthetslära; Solid Mechanics;

    Sammanfattning : In many technical processes, material is deformed under conditions that contain high strain rates. Examples of such processes are collisions, impact, penetration, metal forming and crack propagation. Constitutive models including viscoplasticity have been proposed for these kinds of situations. LÄS MER

  4. 3. Effect of shear cutting on metal fatigue

    Författare :David Gustafsson; Erik Olsson; Jörgen Kajberg; Pär Jonsén; Henrik Sieurin; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Punching; Trimming; Shear cutting; Fatigue; HCF; Residual stresses; Hållfasthetslära; Solid Mechanics;

    Sammanfattning : Lightweighting of automotive and heavy-duty vehicle components is an important task that does not need any further motivation or background. It can be read in a large part of the technical papers in the field. A common approach for finding lighter solutions is to increase the material grade while decreasing the material thickness. LÄS MER

  5. 4. A Study on Sandwich Structures : Development, Mechanical Characterization and Numerical Modeling

    Författare :Samuel Hammarberg; Pär Jonsén; Jörgen Kajberg; Simon Larsson; Dan Zenkert; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Ultra-High Strength Steel; UHSS; Sandwich; Micro-sandwich; Hybrix; Modeling; Composite; Hållfasthetslära; Solid Mechanics;

    Sammanfattning : Legislative demands force the automotive industry to reduce greenhouse gas (GHG) emissions. At the same time, crashworthiness must not be compromised. A ve-hicle’s GHG emissions, such as carbon dioxide, is dependent on its fuel consump-tion. Lowering the vehicle weight, reducing fuel consumption, will therefor reduce emissions. LÄS MER

  7. 5. Towards energy-based fracture modelling for crashworthiness applications

    Författare :Simon Jonsson; Jörgen Kajberg; Stefan Golling; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hållfasthetslära; Solid Mechanics;

    Sammanfattning : The automotive industry is currently adapting to progessively more stringent emission and safety regulations imposed by governmental agencies. This introduces significant design difficulties due to the conflicting nature of passenger safety in automotive manufacturing, namely that increased crashworthiness generally leads to heavier vehicles, which in turn leads to more severe crashes. LÄS MER