Sökning: "fatigue crack propagation"

Visar resultat 1 - 5 av 27 uppsatser innehållade orden fatigue crack propagation.

  1. 1. Life extension of welded steel details in bridges

    Master-uppsats, KTH/Lättkonstruktioner, marina system, flyg- och rymdteknik, rörelsemekanik

    Författare :Zhelei Jin; [2023]
    Nyckelord :Welded joints; Fatigue; Pre-fatigue; Life extension; Fracture mechanics; Finite element analysis; HFMI; ; Svetsade fogar; utmattning; förutmattning; livsförlängning; frakturmekanik; finit elementanalys; HFMI; ;

    Sammanfattning : High-Frequency Mechanical Impacts (HFMI) is a surface treatment technique utilized to introduce residual stresses and extend the service life of structures. This project primarily focuses on studying the life extension effects of HFMI on welded structures that have undergone fatigue and have existing cracks. LÄS MER

  3. 2. Effect of dwell (hold) time on high temperature fatigue crack growth of AM components

    Master-uppsats, KTH/Lättkonstruktioner, marina system, flyg- och rymdteknik, rörelsemekanik

    Författare :Hemanth Venkatesan; [2023]
    Nyckelord :Dwell time; creep; fatigue; IN718; LPBF; hold time; sustained loading; Uppehållstid; krypning; utmattning; IN718; LPBF; hålltid; ihållande belastning;

    Sammanfattning : GKN Aerospace AB, Sweden (GAS) is one of the leading companies taking up the charge in manufacturing components using Additive Manufacturing(ed) (AM) techniques in the aerospace sector. They are a hub of engineering and they are a supplier of engine and engine components to the world’s leading aero-engine manufacturers, and airframes to civil and military aircraft manufacturers. LÄS MER

  4. 3. Correlation between microstructure and fatigue cracks in cast aluminium alloy A205

    Kandidat-uppsats, Jönköping University/Tekniska Högskolan

    Författare :Max Holmberg; Pontus Sundberg; [2022]
    Nyckelord :Aluminium Alloy A205;

    Sammanfattning : Materials research in the aerospace industry is, among other things, focused on reducing the weight and increasing the life of components. Materials with high strength and long lifespan are therefore examined. LÄS MER

  5. 4. Utredning av sprickorsakerna i infästningarna till kylelement

    Kandidat-uppsats, Högskolan i Skövde/Institutionen för ingenjörsvetenskap

    Författare :Ammie Bäckström; Nicklas Werner; [2021]
    Nyckelord :;

    Sammanfattning : The assignment handed out by Cementa in Skövde is to investigate why crack formation and propagation emerge in the fixed attachment clamps and propose solutions against it. The fixed attachments are part of the cooling element suspension, used in the cement production to cool the material coming out of the oven. LÄS MER

  7. 5. Life and fracture in very high cycle fatigue of a high strength steel

    Master-uppsats, Karlstads universitet/Institutionen för ingenjörsvetenskap och fysik (from 2013)

    Författare :Daniel Karlsson; [2021]
    Nyckelord :Very high cycle fatigue; VHCF; Fractography; Fine granular area; FGA; High strength tool steel; Ultrasonic testing equipment;

    Sammanfattning : Classical fatigue models teach that there is an intrinsic fatigue limit for steels, representing a level of stress that is too low for regular crack growth where every cyclic load propagates a fatigue crack through the material. Modern application with extreme lifetimes has shown that fatigue will still take place in steels with stress levels well below the expected fatigue limit. LÄS MER