Sökning: "fatigue"

Visar resultat 1 - 5 av 981 avhandlingar innehållade ordet fatigue.

  1. 1. Oxidation, Creep and Fatigue Synergies in Cast Materials for Exhaust Manifolds

    Författare :Shengmei Xiang; Joakim Odqvist; Baohua Zhu; Stefan Jonsson; Johan Ahlström; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fatigue; low-cycle fatigue; fatigue in an inert atmosphere; fatigue in a synthetic diesel exhaust atmosphere; corrosion-fatigue; creep-fatigue; high-temperature corrosion; high-temperature fatigue; synergistic effect; corrosion-fatigue synergy; creep-fatigue synergy; high-temperature alloys; fatigue damage; creep-fatigue damage; corrosion-fatigue damage; ductile cast iron; high-alloyed austenitic cast steel; thermal cycling; precipitation; aging.; Teknisk materialvetenskap; Materials Science and Engineering;

    Sammanfattning : The future development of engines of heavy-duty vehicles towards reduced CO2 emission will increase the exhaust gas temperature and render the exhaust atmosphere more corrosive. The current service material of exhaust gas components - a ferritic ductile cast iron called SiMo51 - will soon meet its upper-temperature limit. LÄS MER

  3. 2. Fatigue och återhämtning efter hjärtinfarkt

    Författare :Ulla Fredriksson-Larsson; Eva Brink; Pia Alsén; Högskolan Väst; Göteborgs universitet; Gothenburg University; []
    Nyckelord :MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Coping strategies; fatigue; grounded theory; myocardial infarction; nursing; person-centeredness; psychometric evaluation; Rasch analysis; stress; symptom assessment; symptom experience; symptom research; The Multidimensional Fatigue Inventory-20 MFI-20 ; Vårdvetenskap; Nursing science; Fatigue; Myocardial infarction; Symptom experience; Psychometric evaluation;

    Sammanfattning : Fast and efficient acute medical treatment of myocardial infarction (MI) has developed during recent years and has resulted in a reduced number of days spent in hospital and increased survival. To optimize persons’ recovery, secondary preventive strategies are important. LÄS MER

  4. 3. Very high cycle fatigue of high performance steels

    Författare :Vitaliy Kazymyrovych; Karlstads universitet; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; fatigue; tool steels; ultrasonic testing; fatigue life; crack growth rate; fatigue mechanisms; Materialteknik; Materials Engineering;

    Sammanfattning : Many engineering components reach a finite fatigue life well above 109 load cycles. Some examples of such components are found in airplanes, automobiles or high speed trains. For some materials the fatigue failures have lately been found to occur well after 107 load cycles, namely in the Very High Cycle Fatigue (VHCF) range. LÄS MER

  5. 4. Fatigue of steel bridges : New structural details and the implementation of high strength steel

    Författare :Oskar Skoglund; John Leander; Raid Karoumi; Alain Nussbaumer; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; high strength steel; fatigue; steel bridges; steel and concrete composite bridges; new structural details; linear elastic fracture mechanics; effective notch stress method; nominal stress method; Structural Engineering and Bridges; Bro- och stålbyggnad;

    Sammanfattning : The use of high strength steel has the potential to reduce the amount of steel used in bridge structures and thereby facilitate a more sustainable construction. The amount of steel and what steel grade that can be used in bridge structures and other cyclic loaded structures are often limited by a material degradation process called fatigue. LÄS MER

  7. 5. Fatigue strength of engineering materials : the influence of environment and porosity

    Författare :Jan Linder; Bengt Lindberg; Lennart Josefsson; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Stainless steel; cast aluminium; hardened steels; fatigue; corrosion; crack propagation; spot weld; porosity; Other materials science; Övrig teknisk materialvetenskap;

    Sammanfattning : The objective of this work was to use LEFM in order to assess the detrimental influence of surrounding chloride-containing environments for stainless steels, hardened steel as well as for a cast aluminium alloy. An additional aim was also to use LEFM to assess the influence of porosity on the fatigue properties for different commercial cast aluminium alloys and manufacturing methods. LÄS MER