Sökning: "micro crack"

Visar resultat 6 - 10 av 54 avhandlingar innehållade orden micro crack.

  1. 6. Modelling of large deformation crack propagation based on the extended finite element method

    Författare :Martin Fagerström; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; crack propagation; strong discontinuities; material crack driving force; FEM; cohesive zone;

    Sammanfattning : This thesis is concerned with the finite element modelling of large deformation crack propagation, based on the extended finite element methodology. The benefit from this approach is the possibility of locally enriching the finite element space, i.e. to add a priori knowledge about the local behaviour of the solution in order to improve accuracy. LÄS MER

  3. 7. Micro-crack initiation and propagation in fiber reinforced composites

    Författare :Andrejs Pupurs; Stephen L. Ogin; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Polymera konstruktionsmaterial; Polymeric Composite Materials;

    Sammanfattning : Predicting micro-damage initiation and evolution is one of the key challenges for safe design of fiber reinforced polymer composites. Micro-scale damage such as, for example, single fiber break may be unnoticeable and negligible during the initial service life of composite, however, with many loading and unloading cycles this initially micro-scale damage may propagate forming macroscopic scale cracks that can significantly reduce the service lifetime or even lead to unforeseen catastrophic failure of the composite structure. LÄS MER

  4. 8. Microstructure and deformation behaviour of ductile iron under tensile loading

    Författare :Keivan Amiri Kasvayee; Anders E.W. Jarfors; Ehsan Ghassemali; Lennart Elmquist; Kenneth Hamberg; Jönköping University; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Ductile iron; digital image correlation DIC ; in-situ tensile test; pit etching; Microscale deformation; micro-crack; finite elements analysis FEA ; cohesive elements;

    Sammanfattning : The current thesis focuses on the deformation behaviour and strain distribution in the microstructure of ductile iron during tensile loading. Utilizing Digital Image Correlation (DIC) and in-situ tensile test under optical microscope, a method was developed to measure high resolution strain in microstructural constitutes. LÄS MER

  5. 9. The geological conditions for aggregate production, with special focus on blasting and fines production

    Författare :Mathias Jern; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; blasting; in situ block size distribution; fines; aggregates; damage; micro crack; fracture; fragmentation;

    Sammanfattning : .... LÄS MER

  7. 10. Oxidation induced failure of superalloys: High temperature crack growth and oxide scale properties

    Författare :Anand Harihara Subramonia Iyer; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; micromechanical testing; crack growth; Nickel superalloys; scanning electron microscopy; focused ion beam microscopy;

    Sammanfattning : Gas turbine materials are designed to work in extreme environments in high temperature with an oxidising environment and variable mechanical loading. The study of high temperature fatigue properties of these materials is therefore important. LÄS MER