Search for dissertations about: "Material Mechanics"

Showing result 16 - 20 of 710 swedish dissertations containing the words Material Mechanics.

  2. 16. Modelling of Granular Materials

    Author : Aylin Ahadi; Mekanik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; hydraulic engineering; Civil engineering; materialteknik; Materiallära; Material technology; binary mixture model; simulations; material modelling; finite element; granular materials; offshore technology; soil mechanics; Väg- och vattenbyggnadsteknik;

    Abstract : The aim of this doctoral study is to develop and implement a material model for granular materials. The course of this work was concentrated upon a non-associated plasticity model with yield surface and the flow potential expressed in terms of the mean stress p and the third stress invariants I3. READ MORE

  4. 17. Discrete element modelling of the mechanical behaviour of lithium-ion battery electrode layers

    Author : Axel Lundkvist; Per-Lennart Larsson; Pär Jonsén; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Lithium-ion batteries; mechanical characterisation; simulations; contact mechanics; discrete element method; Litiumjonbatterier; mekanisk karakterisering; simuleringar; kontaktmekanik; diskret elementmetod; Teknisk mekanik; Engineering Mechanics; Solid Mechanics; Hållfasthetslära;

    Abstract : Since their introduction in the late 20th century, lithium-ion batteries have become the leading battery technology for portable devices and electric vehicles due to their high energy density and rechargeability. However, the increasing demand for a longer battery life span is hindered by the fading of the battery’s charge capacity over prolonged use. READ MORE

  5. 18. Coupled vibrations in horizontal and vertical rotor-bearings systems

    Author : Jean-Claude Luneno; Magnus Karlberg; Luleå tekniska universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Technology - Engineering mechanics; Teknikvetenskap - Teknisk mekanik; Hållfasthetslära; Solid Mechanics;

    Abstract : For dynamical systems having several degrees of freedom, motion in one direction can induce motion in the other and/or vice versa. This means that there is a certain coupling between these two motions. Coupling can in some cases be a source of instability that causes self-excited vibrations in rotating machinery. READ MORE

  6. 19. Acoustical Measurements of Material Nonlinearity and Nonequilibrium Recovery

    Author : Kristian Haller; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nonlinear acoustics; nondestructive testing; activation density; slow dynamics; nonequilibrium recovery; resonance frequency; nonlinear wave modulation spectroscopy; harmonic generation; trapped modes; open resonator; sweep rate; constant strain sweep;

    Abstract : A damaged material or a material with non perfect atomic geometry, dislocations or cracks, exhibits two types of characteristic responses to acoustic excitations. First is the fast nonlinear dynamics response that is present as long as the material is excited. As soon as the excitation stops the response disappear. READ MORE

  7. 20. Fatigue crack growth experiments and analyses - from small scale to large scale yielding at constant and variable amplitude loading

    Author : Pär Ljustell; Fred L. Nilsson; Bo Alfredsson; Gunnar Härkegård; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fracture mechanics; fatigue crack growth; finite elements analysis; small scale yielding SSY ; large scale yielding LSY ; low cycle fatigue LCF ; crack tip opening displacement CTOD ; crack closure; potential drop method; constant amplitude load; variable amplitude load; inconel 718; stainless steel 316L;

    Abstract : This thesis is on fatigue crack growth experiments and assessments of fatigue crack growth rates. Both constant and variable amplitude loads in two different materials are considered; a nickel based super-alloy Inconel 718 and a stainless steel 316L. READ MORE