Sökning: "elastic solids"

Visar resultat 1 - 5 av 35 avhandlingar innehållade orden elastic solids.

  1. 1. Vibrations in solids : From first principles lattice dynamics to high temperature phase stability

    Författare :Nina Shulumba; Magnus Odén; Igor Abrikosov; Frank Mücklich; Matteo Calandra; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : In this thesis I introduce a new method for calculating the temperature dependent vibrational contribution to the free energy of a substitutionally disordered alloy that accounts for anharmonicity at high temperatures. This method exploits the underlying crystal symmetries in an alloy to make the calculations tractable. LÄS MER

  3. 2. Mechanical Characterization of Engineering Materials by Modal Testing

    Författare :Daniel Larsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; material variability; modal testing; non-destructive test methods; damping ratios; timber beams; plastic panels; aluminium panel; elastic constants; concrete curing; wood-based panels; solids; high-strength concrete; anisotropic materials;

    Sammanfattning : This thesis deals with the use of modal testing for establishing elastic constants of engineering materials and for indicating material variability in terms of stiffness and damping properties. The methodology using modal testing techniques, is applied to timber beams, high strength concrete prisms, wood-based panels (oriented strand board and chipboard), an aluminium alloy panel and plastic laminate panels (high-pressure laminate). LÄS MER

  4. 3. Disordered Icosahedral Boron-Rich Solids : A Theoretical Study of Thermodynamic Stability and Properties

    Författare :Annop Ektarawong; Björn Alling; Michael Widom; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Icosahedral boron-rich solids; Boron carbide; Configurational disorder; First-principles calculations; Thermodynamic stability; Superatom-special quasirandom structure;

    Sammanfattning : This thesis is a theoretical study of configurational disorder in icosahedral boron-rich solids, in particular boron carbide, including also the development of a methodological framework for treating configurational disorder in such materials, namely superatom-special quasirandom structure (SA-SQS). In terms of its practical implementations, the SA-SQS method is demonstrated to be capable of efficiently modeling configurational disorder in icosahedral boron-rich solids, whiles the thermodynamic stability as well as the properties of the configurationally disordered icosahedral boron-rich solids, modeled from the SA-SQS method, can be directly investigated, using the density functional theory (DFT). LÄS MER

  5. 4. Structural stability of solids from first principles theory

    Författare :Blanka Magyari-Köpe; KTH; []
    Nyckelord :density functional theory; electronic structure; high pressure; perovskite structure; phase transition; structural stability; geophysics; binary alloys; elastic constants;

    Sammanfattning : .... LÄS MER

  7. 5. Modeling of Scattering by Cracks in Anisotropic Solids - Application to Ultrasonic Detection

    Författare :Johan Mattsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; elastic wave; ultrasonics; crack; integral equations; transducer; anisotropy; scattering; nondestructive testing;

    Sammanfattning : Elastodynamic wave scattering in anisotropic solids with application to ultrasonic nondestructive testing (NDT) is treated and mathematically modeled in this thesis. The scatterers are infinite strip-like cracks and the solids are homogeneous and linearly elastic with negligible damping. LÄS MER