Sökning: "micro crack"

Visar resultat 1 - 5 av 54 avhandlingar innehållade orden micro crack.

1. 1. High Strain Fatigue Crack Growth and Crack Closure

   Författare :Michael Andersson; Materialteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; materialteknik; Materiallära; Material technology; crack closure; high strain fatigue; crack grotwh;

   Sammanfattning : Understanding of the growth of fatigue cracks is of utmost importance since such growth often has a profound influence on the life of components subjected to cyclic loading. Thus, reliable fatigue life models enable a more efficient use of materials and improve the performance and efficiency in many applications. LÄS MER

3. 2. The role of microstructure for crack propagation in cortical bone

   Författare :Anna Gustafsson; Avdelningen för Biomedicinsk teknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Crack deflection; Interface; Mechanical testing; Micro-CT; Osteon; Porosity; XFEM;

   Sammanfattning : Healthy cortical bone tissue is both tough and strong and has a unique ability to resist fracture. One reason is the hierarchical structure of the tissue where toughening mechanisms at all length scales act to slow down or stop a propagating crack. LÄS MER

4. 3. Predicting shear type crack initiation and growth in concrete with non-linear finite element method

   Författare :Richard Malm; Håkan Sundquist; Anders Ansell; Kent Gylltoft; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; non-linear finte element analysis; concrete; crack width; crack propagation; shear; Building engineering; Byggnadsteknik;

   Sammanfattning :   In this thesis, the possibility to numerically describing the behaviour that signifies shear type cracking in concrete is studied. Different means for describing cracking are evaluated where both methods proposed in design codes based on experiments and advanced finite element analyses with a non-linear material description are evaluated. LÄS MER

5. 4. On the deformation behavior and cracking of ductile iron; effect of microstructure

   Författare :Keivan Amiri Kasvayee; Anders E.W. Jarfors; Jens Bergström; Jönköping University; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Spherical graphite iron; component casting; high silicon ductile iron; digital image correlation DIC ; in-situ tensile testing; in-situ cyclic testing; DIC pattern generation; pit etching; micro-scale deformation; micro-crack; finite element analysis FEA ; focused ion beam FIB milling; segjärn; komponentgjutning; högkisellegerat segjärn; digital image correlation DIC ; insitu dragprovning; in-situ cyklisk provning; DIC-mönstergenerering; grop-etsning; mikroskalig deformation; mikrosprickor; finite element analys FEA ; fokuserad jonstråle FIB avverkning;

   Sammanfattning : This thesis focuses on the effect of microstructural variation on the mechanical properties and deformation behavior of ductile iron. To research and determine these effects, two grades of ductile iron, (i) GJS-500-7 and (ii) high silicon GJS-500-14, were cast in a geometry containing several plates with different section thicknesses in order to produce microstructural variation. LÄS MER

7. 5. Bright Lights: Innovative Micro- and Nano-Patterning for Sensing and Tissue Engineering

   Författare :Alessandro Enrico; Göran Stemme; Frank Niklaus; Anna Herland; Jürgen Brugger; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Micro-electromechanical systems MEMS ; nanotechnology; nanowires; microfabrication; tissue engineering; crack-lithography; direct writing; femtosecond lasers; two-photon polymerization; 3D micromachining; cavitation molding; scalable optical patterning; 2D materials; surface structuring; bacterial-surface interaction.; Electrical Engineering; Elektro- och systemteknik;

   Sammanfattning : Light is the primary source of energy on our planet and has been a significant driver in the evolution of human society and technology. Light finds applications in two-dimensional (2D) photolithography and three-dimensional (3D) printing, where a pattern is transferred to a material of interest by ultraviolet (UV) light exposure, and in laser scribing and cutting, where high power lasers are used to pattern the surface of objects or cut through the bulk of the material of interest. LÄS MER