Search for dissertations about: "fracture crack steel"

Showing result 1 - 5 of 55 swedish dissertations containing the words fracture crack steel.

  2. 1. Modelling of fracture toughness using peridynamics : A Study of J-integral, essential work and homogenisation

    Author : Christer Stenström; Pär Jonsén; Kjell Eriksson; Ugo Galvanetto; Luleå tekniska universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Peridynamics; J-integral; Essential work of fracture; Nonlocal methods; Meshless; Meshfree; Fracture; Crack tip; Exact analytical; Center cracked tension; Double edge notched tensile; fracture toughness; Peridynamik; Brottmekanik; Sprickspets; Brottseghet; Spänningsintensitet; Hållfasthetslära; Solid Mechanics;

    Abstract : Fracture toughness is one of the most important properties of a material. Being able toaccurately estimate the energy that goes into forming new crack surfaces is essential for the development of new materials, quality assurance, structural monitoring and failure analysis. READ MORE

  4. 2. Fatigue life extension in existing steel bridges. High-Frequency Mechanical Impact treatment and Tungsten Inert Gas remelting in life extension and fatigue crack repair of welded steel structures

    Author : Hassan al-Karawi; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HFMI; TIG-dressing; Life extension; Post weld treatment; Gain factor; Linear elastic fracture mechanics; Crack retrofiting; Peening; fatigue crack; Crack detection; Microhardness; Concentration factor; LEFM; TIG-remelting; Strain gauge;

    Abstract : This thesis investigates the performance of improved welds with two post-weld treatment methods for application on existing structures. High-Frequency Mechanical Impact (HFMI) treatment and Tungsten Inert Gas (TIG) remelting were used for fatigue life extension of welded structures. READ MORE

  5. 3. 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

  6. 4. Toughness of Tool Steel

    Author : Henrik Jesperson; Håkan Engqvist; Birger Karlsson; Uppsala universitet; []
    Keywords : Toughness; Tool Steel; Heat Treatment; Temperature; Energy absorption; Impact Testing; Fracture Toughness Testing; Non-metallic Inclusions; Carbides; Nitrides; Statistics; TECHNOLOGY; TEKNIKVETENSKAP; Teknisk fysik med inriktning mot materialvetenskap; Engineering Science with specialization in Materials Science;

    Abstract : Toughness is the ability to resist tensile stresses in the presence of a notch or crack. Sometimes gross cracking of industrial tools, mould or dies, occurs due to insufficient toughness. As the economic consequences of the gross cracking are serious, the toughness of industrial tool material, generally tool steel, is of paramount importance. READ MORE

  7. 5. High-Temperature Durability Prediction of Ferritic-Martensitic Steel

    Author : Ahmed Azeez; Robert Eriksson; Kjell Simonsson; Daniel Leidermark; Christer Persson; Linköpings universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Ferritic-martensitic steel; Low cycle fatigue; Thermomechanical fatigue; Crack propagation; Fracture mechanics; Finite element modelling;

    Abstract : Materials used for high-temperature steam turbine sections are generally subjected to harsh environments with temperatures up to 625 °C. The superior creep resistance of 9–12 % Cr ferritic-martensitic steels makes them desirable for those critical steam turbine components. READ MORE