Sökning: "J-integral"

Visar resultat 11 - 15 av 19 avhandlingar innehållade ordet J-integral.

  1. 11. On the Modelling of Fracture Using Strong Discontinuities

    Författare :Martin Fagerström; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fracture; strong discontinuity; material forces; finite deformations; FEM;

    Sammanfattning : The major concern of this work is the constitutive and numerical modelling of fracture,based on strong discontinuity formulations. More particularly, an extended finiteelement approach is used, where the total displacement is separated in two mutuallyindependent fields, representing the continuous and discontinuous displacement respectively. LÄS MER

  3. 12. Constitutive behaviour and fracture toughness of an adhesive layer

    Författare :Anders Biel; Högskolan i Skövde; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; adhesive layer; DCB-specimen; experimental method; modus I; peel; standardized methods; damage zone; stress whitening; Engineering mechanics; Teknisk mekanik; Teknik; Technology;

    Sammanfattning : This report presents the fracture energy and the complete stress – elongation relation for a structural adhesive loaded in modus I. The experiments are performed on the Double Cantilever Beam (DCB) specimen and the method to analyse the experiments is based on the J-integral approach which means that the energy release rate, i.e. LÄS MER

  4. 13. Thermo-mechanical Fatigue Crack Propagation in Inconel 718

    Författare :Lars Jacobsson; Materialteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; crack closure; image analysis; potential drop; in-situ scanning elecron microscopy; crack propagation experiments; Thermo-mechanical fatigue; Inconel 718;

    Sammanfattning : Thermo-mechanical fatigue crack propagation in Inconel 718 has been studied with different methods. In-situ observations with a scanning electron microscope (SEM) were performed, the crack propagation process was followed cycle by cycle and the influences from load, temperature, and microstructure on the crack growth were analyzed. LÄS MER

  5. 14. A study on contact fatigue mechanisms

    Författare :Bo Alfredsson; KTH; []
    Nyckelord :contact fatigue mechanism; spall; spalling; surface crakc; sub-surface crack; elesto-plastic indentation; contact compliance measurement; TECHNOLOGY; TEKNIKVETENSKAP;

    Sammanfattning : Surfaces subjected to rolling and sliding contacts maysuffer from contact fatigue. This thesisdeals with solidmechanic aspects of contact fatigue including the descriptionand verificationof explaining mechanisms. The new mechanism forsurface initiated contact fatigue is basedon tensile surfacestresses from local asperity contacts. LÄS MER

  7. 15. Fiber/matrix interface crack propagation in polymeric unidirectional composite

    Författare :Linqi Zhuang; Anders Holmberg; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Polymera konstruktionsmaterial; Polymeric Composite Materials;

    Sammanfattning : Fiber/matrix interface cracking plays an important role in determining the final failure of unidirectional composites. In the present study, energy release rate (ERR) for fiber/matrix interface debond growth originated from fiber break in unidirectional composite is calculated using 5-cylinders axisymmetric and 3-D FEM models with hexagonal fiber arrangement. LÄS MER