Sökning: "Fatigue crack propagation."

Visar resultat 11 - 15 av 104 avhandlingar innehållade orden Fatigue crack propagation..

  1. 11. 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

    Författare :Hassan al-Karawi; Chalmers tekniska högskola; []
    Nyckelord :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;

    Sammanfattning : 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. LÄS MER

  3. 12. Corrosion Fatigue of Stainless Steels

    Författare :Jan Linder; KTH; []
    Nyckelord :Stainless steel; corrosion fatigue; crack propagation; spot weld;

    Sammanfattning : The aim of this work was to investigate the effect ofchloride-containing environments on corrosion fatigueproperties for different stainless steels grades. The steelsinvestigated ranged from the standard 304 grade to thesuperaustenitic 654SMO and the superduplex SAF2507. LÄS MER

  4. 13. Numerical simulation of crack propagation and wear in rails

    Författare :Jim Brouzoulis; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wear; Rolling Contact Fatigue; crack propagation; railway mechanics;

    Sammanfattning : This thesis is concerned with rail deterioration due to Rolling Contact Fatigue (RCF) and wear. Focus lies primarily on numerical modelling and prediction, with the long-term objective of developing tools to be used for specifications and planning of rail maintenance. LÄS MER

  5. 14. Continuous Welded Railway Rails: Residual Stress Analyses, Fatigue Assessments and Experiments

    Författare :Anders Skyttebol; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; microstructure; laser cladding; plasticity; rolling contact; computational welding mechanics; materials testing; flash butt welding; fatigue; railway rails; fatigue crack propagation; finite element method;

    Sammanfattning : Railway rails are today often continuously welded. This type of joint generally requires less maintenance than is needed for the bolted joints. It has also reduced wheel damage and made the ride more comfortable. However, these joints are subject to damage. LÄS MER

  7. 15. Very high cycle fatigue of automotive steels : Testing and computation at 20 kHz

    Författare :Mohamed Sadek; Jens Bergström; Nils Hallbäck; Ulrich Krupp; Karlstads universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Very high cycle fatigue; ultrasonic fatigue testing; automotive steels; fatigue strength; stress intensity computation; crack growth; Materialteknik; Materials Engineering;

    Sammanfattning : Mechanical fatigue failure occurs in components subjected to cyclic loading. A crack initiates at critical regions in the component and propagates during repeated loading. The expected fatigue life depends on the level, type and frequency of the loading. LÄS MER