Sökning: "finite size effects"

Visar resultat 1 - 5 av 109 avhandlingar innehållade orden finite size effects.

  1. 1. Modelling and simulation of plastic deformation on small scales : interface conditions and size effects of thin films

    Författare :Per Fredriksson; Peter Gudmundson; Christian Niordson; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Strain gradient plasticity; Size effects; Thin films; Interface; Finite element method; Dislocations; Constitutive behaviour; Hardening behaviour; Indentation; Contact mechanics; Metal matrix composites; Engineering mechanics; Teknisk mekanik;

    Sammanfattning : Contrary to elastic deformation, plastic deformation of crystalline materials, such as metals, is size-dependent. Most commonly, this phenomenon is present but unnoticed, such as the effect of microstructural length scales. LÄS MER

  3. 2. A study of finite-size and non-perturbative effects on the van der Waals and the Casimir-Polder forces

    Författare :Thiyam Priyadarshini; Clas Persson; Mathias Boström; Thomas Ederth; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; finite-size effects; non-perturbative theory; van der Waals and Casimir Polder forces; Teknisk materialvetenskap; Materials Science and Engineering;

    Sammanfattning : This licentiate thesis addresses two important aspects of the van der Waals and the Casimir-Polder ground-state and excited-state (resonance) interactions between two atoms or molecules. The first is the finite-size effect and the second is the non-perturbative effect. LÄS MER

  4. 3. Hydrogen in nano-sized metals : Diffusion and hysteresis effects

    Författare :Wen Huang; Björgvin Hjörvarsson; Max Wolff; Gavin Walker; Uppsala universitet; []
    Nyckelord :Hydrogen; diffusion; hysteresis; optical technique; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : Metal hydrides can be used as hydrogen storage materials for fuel cells and batteries, and as sensors for detecting hydrogen gas. The use of metal hydrides for hydrogen storage can be hindered by poor kinetics and low capacity. Moreover, poor sensitivity, long recovery and response time, limit the applications of metal hydrides as hydrogen sensors. LÄS MER

  5. 4. FEM Modelling of Micro-galvanic Corrosion in Al Alloys Induced by Intermetallic Particles : Exploration of Chemical and Geometrical Effects

    Författare :Litao Yin; Jinshan Pan; Christopher Leygraf; Ying Jin; Herman Terryn; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Finite Element Method FEM ; Modelling; Micro-galvanic corrosion; Al alloy; corrosion product deposition; chemical factors; steric hindrance effect; Kemi; Chemistry;

    Sammanfattning : Localized corrosion, such as pitting, crevice corrosion or galvanic corrosion, is a long-standing phenomenon that can greatly limit the life of metallic materials. For decades experimental methods have been used to try to understand the underlying physical, chemical and electrochemical processes that control localized corrosion in order to find effective protection methods against its propagation. LÄS MER

  7. 5. On failure modelling in finite element analysis : material imperfections and element erosion

    Författare :Mattias Unosson; Larsgunnar Nilsson; Kjell Simonsson; Lars Olovsson; Anders Eriksson; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; finite element method; element erosion; material failure; material imperfections; crack-tip; Solid mechanics; Fastkroppsmekanik;

    Sammanfattning : This dissertation concerns failure modelling with material imperfections and element erosion in finite element analyses. The aim has been to improve the element erosion technique, which is simple to use and implement and also computationally inexpensive. LÄS MER