Sökning: "Very high cycle fatigue"

Visar resultat 1 - 5 av 24 avhandlingar innehållade orden Very high cycle fatigue.

  1. 1. Very high cycle fatigue of high performance steels

    Författare :Vitaliy Kazymyrovych; Karlstads universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; 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

  2. 2. 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

  3. 3. Very high cycle fatigue of tool steels

    Författare :Vitaliy Kazymyrovych; Jens Bergström; Arne Melander; Karlstads universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fatigue; crack growth; ultrasonic testing; tool steels; inclusions; Materialteknik; Materials Engineering;

    Sammanfattning : An increasing number of engineering components are expected to have fatigue life in the range of 107 - 1010 load cycles. Some examples of such components are found in airplanes, automobiles and high speed trains. LÄS MER

  4. 4. Very high cycle fatigue of duplex stainless steels and stress intensity calculations

    Författare :Muhammad Waqas Tofique; Jens Bergström; Nils Hallbäck; Anders Gåård; Johan Moverare; Karlstads universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Very high cycle fatigue; duplex stainless steel; ultrasonic fatigue testing; distributed dislocation dipole technique; Materialteknik; Materials Engineering;

    Sammanfattning : Very high cycle fatigue (VHCF) is generally considered as the domain of fatigue lifetime beyond 10 million (107) load cycles. Few examples of structural components which are subjected to 107-109 load cycles during their service life are engine parts, turbine disks, railway axles and load-carrying parts of automobiles. LÄS MER

  5. 5. High-Temperature Corrosion-Fatigue of Cast Alloys for Exhaust Manifolds

    Författare :Shengmei Xiang; Joakim Odqvist; Baohua Zhu; Johan Ahlström; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; High temperature; corrosion fatigue; low-cycle fatigue; cast alloys; high-temperature oxidation; intermetallic phase; Teknisk materialvetenskap; Materials Science and Engineering;

    Sammanfattning : The introduction of gas-driven Otto engine and the corresponding usage of bio-fuels in heavy-duty engines will render the exhaust atmosphere more corrosive and bring a higher working temperature to exhaust manifolds. The current service material, a ferritic ductile cast iron called SiMo51, will soon meet its upper temperature limit set by the ferrite-austenite transformation at 860ºC. LÄS MER