Search for dissertations about: "Viscoplasticity"

Showing result 1 - 5 of 28 swedish dissertations containing the word Viscoplasticity.

  1. 1. Modeling of Inelastic Response of Metals with Emphasis on Cyclic Viscoplasticity

    Author : Magnus Ekh; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; large strains; integration; anisotropy; plasticity; creep; viscoplasticity; kinematic hardening; metals; damage; calibration;

    Abstract : This thesis is concerned with the continuum modeling of the macroscopic behavior of engineering metals, in particular as part of life prediction strategies. Focus is primarily placed on the formulation and numerics of models for cyclic rate-dependent response. READ MORE

  2. 2. Experiments and modelling of fracture initiation at impact

    Author : Ola Wall; Hållfasthetslära; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vibration and acoustic engineering; vacuum technology; hydraulics; Viscoplasticity; Mechanical engineering; Ductile; Brittle; Dynamic; Fracture; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik; Material technology; Materiallära; materialteknik;

    Abstract : The thesis addresses different questions, each necessary in the understanding of dynamic fracture initiation and crack propagation in steel. Emphasis lays on dynamic crack propagation experiments performed in the ductile to brittle transition region and possible conclusions, that can be drawn from them. READ MORE

  3. 3. Modelling of cyclic and viscous behaviour of thermomechanically loaded pearlitic steels; Application to tread braked railway wheels

    Author : Ali Esmaeili; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; rolling contact fatigue; plasticity; tread braking; full-scale brake rig testing; Railway wheels; finite element analyses; pearlitic steel; viscoplasticity; ratchetting; phase transformations;

    Abstract : In service, railway wheel and rail materials are subjected to high stresses and, in some cases, elevated temperatures. The high stresses are caused by the rolling contact between wheel and rail. Furthermore, heat generated from tread braking and/or sliding between wheel and rail gives additional stress due to constrained thermal expansion. READ MORE

  4. 4. Modelling of cyclic and viscous behaviour of pearlitic steels. Application to tread braked railway wheels

    Author : Ali Esmaeili; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Railway wheels; viscoplasticity; tread braking; rolling contact fatigue; full-scale brake rig testing; finite element analysis; plasticity;

    Abstract : Railway wheel and rail materials are subjected to very high stresses and, in some cases, also elevated temperatures. The rolling contact loading results in a multiaxial stress state with a combination of compression and shear. READ MORE

  5. 5. A Damage-Based Interface Model: Application to the Degradation and Failure of a Polycrystalline Microstructure

    Author : Patrik Cannmo; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; damage; polycrystalline microstructure; degradation; slip and dilatation; interfaces; FE-calculations; viscoplasticity; plasticity; failure;

    Abstract : A constitutive model for material interfaces is presented. The model is based on damage coupled to plastic (or viscoplastic) slip and dilatation, and it is able to describe the successive degradation and failure of an interface. READ MORE