Sökning: "case hardening"

Visar resultat 21 - 25 av 64 avhandlingar innehållade orden case hardening.

  1. 21. Martensitic Transformation in High Carbon Steels - Martensite Tetragonality and Impact of Cooling Rate

    Författare :Thomas Kohne; Annika Borgenstam; Peter Hedström; Jilt Sietsma; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; High carbon steel; Martensitic transformation; Martensite tetragonality; Fatigue performance; Materials Science and Engineering; Teknisk materialvetenskap;

    Sammanfattning : Case-hardened gears are an essential part of our every day life in their role of power transmission in cars and heavy-duty trucks. The increasing use of low pressure carburizing (LPC) for case-hardening in combination with high pressure gas quenching (HPGQ) for cooling opens new possibilities in the design of heat treatments for improved fatigue performance. LÄS MER

  3. 22. Fundamental friction phenomena and applied studies on tribological surfaces

    Författare :Viktoria Westlund; Staffan Jacobson; Sture Hogmark; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Teknisk fysik med inriktning mot tribomaterial; Engineering Science with specialization in Tribo Materials;

    Sammanfattning : This thesis is based on two different projects, one more focused on applied research and one on more basic research. The first project examines the po- tential of nitriding as an alternative to case hardening in tribologically loaded components while the second project involves micro scale studies of the relations between roughness, transfer and friction between metals. LÄS MER

  4. 23. On the Simulation of Progressive Deformation in Nuclear Piping

    Författare :Andreas Gustafsson; Jan Granlund; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Steel Structures; Stålbyggnad;

    Sammanfattning : In this thesis the performance of different constitutive models in ratchet simulation is investigated. Ratcheting is accumulated plastic strains which may occur when a structure is subjected to a constant load in combination with cyclic loading. LÄS MER

  5. 24. Stresses in high performance concrete due to temperature and moisture variations at early ages

    Författare :Hans Hedlund; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Structural Engineering; Konstruktionsteknik;

    Sammanfattning : This thesis presents results from laboratory tests and numerical analyses of stress states in concrete structures arising from volume changes due to temperature and shrinkage during hydration. The laboratory tests presented here deal with: the determination of heat transfer coefficients for cooling pipes measurements of self-desiccation and shrinkage under sealed conditions deformation measurements under temperature and moisture changes and measurements of stress development during hardening for a fully restrained structural member. LÄS MER

  7. 25. Variation Simulation Customized for Composites by Including FEM Simulations of Orthotropic Lamina

    Författare :Cornelia Jareteg; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Geometry assurance; FEM; Composites; Shell model; Process variation; Method of Influence Coefficients; Monte Carlo; Orthotropic material; Manufacturing; Tolerance analysis; Variation simulation; Spring-in; Tolerance analysis;

    Sammanfattning : The use of composite materials is increasing in many fields of production. Composite manufacturing, as well as other fields of production, suffers from uncertainties resulting in products that deviate from the specification. Geometry assurance is a common procedure used to keep the variations in product assemblies under control. LÄS MER