Sökning: "contact fatigue mechanism"

Visar resultat 16 - 20 av 24 avhandlingar innehållade orden contact fatigue mechanism.

  1. 16. Diesel Engnine Cam and Roller Follower Tribology

    Författare :Martin Olsson; Maskinelement; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vibration and acoustic engineering; vacuum technology; hydraulics; Cam; Roller follower; Mechanical engineering; Damage progress; Running in; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik;

    Sammanfattning : Surfaces subjected to rolling and sliding contacts may suffer from contact fatigue. The cam and roller follower mechanism is a typical rolling and sliding contact. LÄS MER

  3. 17. Fracture Mechanics in Design and Assessment of Existing Structures: Two Case Studies

    Författare :Pourya Noury; Raid Karoumi; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Steel Structures; Stålbyggnad;

    Sammanfattning : In the present thesis, the application of fracture mechanics in design and assessment of steel structures has been studied.The first case study concerns a ring-flange connection used in wind turbine towers. The flange is rolled from straight steel profile into a complete ring. LÄS MER

  4. 18. On failure of high strength steel bridge roller bearings

    Författare :Pourya Noury; Ove Lagerqvist; Kjell Eriksson; John Yates; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Stålbyggnad; Steel Structures;

    Sammanfattning : This thesis is concerned with failure analysis of high strength steel bridge roller bearings.Paper Adescribes how the commonly used Hertz formulas for contact stresses underestimate the actual stresses in practice due to temperature differences, misalignments and other construction-related conditions. LÄS MER

  5. 19. Additive Manufacturing of Ni-Fe Superalloys : Exploring the Alloying Envelope and the Impact of Process on Mechanical Properties

    Författare :Carl Johan Hassila; Urban Wiklund; Staffan Jacobson; Johan Moverare; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Additive manufacturing; alloying for AM; PBF-LB; microstructure; tensile and impact testing; Teknisk fysik med inriktning mot tribomaterial; Engineering Science with specialization in Tribo Materials;

    Sammanfattning : Additive manufacturing of metals has received a lot of attention in the last decade as this family of manufacturing processes allows the manufacturing of complicated geometries which would be difficult to produce using conventional manufacturing techniques. Additive manufacturing of the Ni-Fe based superalloys 625 and 718 using the Powder Bed Fusion – Laser Beam (PBF-LB) process is facilitated by the fact that these alloys were developed as weldable alternatives to other high-strength, high-temperature Ni-based superalloys. LÄS MER

  7. 20. Efficiency and wear properties of spur gears made of powder metallurgy materials

    Författare :Li Xinmin; Ulf Olofsson; Giovanni Straffelini; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Powder Metallurgy Gears; Efficiency; Wear; Friction; Porosity Structure; FZG gear test rig; Machine Design; Maskinkonstruktion;

    Sammanfattning : Powder metallurgy (PM) is usually used in manufacturing parts with complex geometries, such as gears and structural parts. The main attractions of PM are the high rate of material utilization, environmental friendliness of production, economic advantages (especially for complex geometries), and possibility of obtaining lighter components. LÄS MER