Search for dissertations about: "Elastic Constants"

Showing result 1 - 5 of 68 swedish dissertations containing the words Elastic Constants.

  1. 1. Local variability in chemical and physical properties of spruce wood fibers

    Author : Anna Bergander; KTH; []
    Keywords : cell walls; chemical composition; elastic constants; elastic strength; Fiber properties; Fibril angles; Mathematical models; Microscopy techniques; Picea Abies; Stiffness; Tensile properties; Wood polymers; Wood;

    Abstract : Wood is well known to be a heterogeneous native materialwith large variations in its composite properties, includingvariations whose origins have not yet been completelyidentified. Traditionally, the macroscopic variations in woodhave received the most attention; for example, the variation indensity from the pith to the bark in trees. READ MORE

  2. 2. Thermodynamic and kinetic properties of Fe-Cr and TiC-ZrC alloys from Density Functional Theory

    Author : Vsevolod Razumovskiy; Pavel Korzhavyi; Andrei Ruban; Malin Selleby; Sergei Dudarev; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; ab initio; first principles; point defects; vacancy clusters; alloys; steels; iron; carbides; diffusion; phase diagram; density functional theory; elastic constants; elastic properties; thermodynamic modelling;

    Abstract : The complete and accurate thermodynamic and kinetic description of any systemis crucialfor understanding and predicting its properties. A particular interest is in systemsthat are used for some practical applications and have to be constantly improved usingmodification of their composition and structure. READ MORE

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

    Author : Daniel Larsson; Chalmers tekniska högskola; []
    Keywords : 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;

    Abstract : 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). READ MORE

  4. 4. Static and time-dependent mechanical behaviour of preserved archaeological wood : Case studies of the seventeenth century warship Vasa

    Author : Alexey Vorobyev; Kristofer Gamstedt; Eiichi Obataya; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; archaeological wood; compression test; cubic samples; elastic constants; oak wood; barrelling formation; quasi-static loading; resonant ultrasound spectroscopy RUS ; Vasa ship; creep; 3D laser scanning; Time-dependent behaviour;

    Abstract : Wooden objects have been widely used in the history of humanity and play an important role in our cultural heritage. The preservation of such objects is of great importance and can be a challenging task. This thesis investigates the static and time-dependent mechanical behaviour of archaeological oak wood from the Vasa warship. READ MORE

  5. 5. Effects of disorder in metallic systems from First-Principles calculations

    Author : Christian Asker; Igor Abrikosov; Jörg Neugebauer; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Iron; Nickel; Magnesium; Manganese; Molybdenum; Zirconium; Elastic Constants; High pressure; Earth s core; Density-functional theory; Ab-initio; First-Principles; Core-level shifts; Molecular Dynamics; Phonons; Dynamical Instability; Condensed matter physics; Kondenserade materiens fysik; Computational physics; Beräkningsfysik;

    Abstract : In this thesis, quantum-mechanical calculations within density-functional theory on metallic systems are presented. The overarching goal has been to investigate effects of disorder. In particular, one of the properties investigated is the bindingenergy shifts for core electrons in binary alloys using different theoretical methods. READ MORE