Sökning: "gradient hardening"

Visar resultat 1 - 5 av 24 avhandlingar innehållade orden gradient hardening.

  1. 1. Hardening of Carbon Steel by Water Impinging Jet Quenching Technique : Differential Cooling of Steel Sheets and Quenching of Cylindrical Bars

    Författare :Pavel Romanov; Mattias Calmunger; Bahram Moshfegh; Viktor Norman; Ru Peng; Peter Hedström; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Differential cooling; Impinging jet quenching; Microstructure gradient; Hardening;

    Sammanfattning : Austenitization followed by quenching is a well-known conventional heat-treating procedure which is widely used on carbon steels with the aim to obtain high strength in as-quenched condition. Such quenching is usually done by immersing a steel product into the cooling medium which provides a uniform cooling of the surface. LÄS MER

  3. 2. Computational modeling of polycrystals using gradient crystal plasticity

    Författare :Mikkel Grymer; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; parallel algorithms; crystal plasticity; dual mixed finite element method; gradient hardening; grain modeling;

    Sammanfattning : This thesis treats the modeling of grain size dependence inmicrostructure models of metals. It is shown how gradient hardening, in a thermodynamically consistent fashion, can be included into a crystal plasticity model, which is used as the constitutive model in each grain of the polycrystal. LÄS MER

  4. 3. Modeling and experimental characterization of large biaxial strains and induced anisotropy in pearlitic rail steel

    Författare :Knut Andreas Meyer; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Pearlitic steel; yield criteria; distortional hardening; axial-torsion; kinematic hardening; biaxial loading; hyperelasto-plasticity;

    Sammanfattning : Large shear strains accumulate in the near-surface region under the running band of railway rails. In this region, rolling contact fatigue cracks often initiate, causing major problems for the railway industry. LÄS MER

  5. 4. Modelling and simulation of plastic deformation on small scales : interface conditions and size effects of thin films

    Författare :Per Fredriksson; Peter Gudmundson; Christian Niordson; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Strain gradient plasticity; Size effects; Thin films; Interface; Finite element method; Dislocations; Constitutive behaviour; Hardening behaviour; Indentation; Contact mechanics; Metal matrix composites; Engineering mechanics; Teknisk mekanik;

    Sammanfattning : Contrary to elastic deformation, plastic deformation of crystalline materials, such as metals, is size-dependent. Most commonly, this phenomenon is present but unnoticed, such as the effect of microstructural length scales. LÄS MER

  7. 5. Continuum modelling of work hardening in precipitation hardened alloys

    Författare :Philip Croné; Jonas Faleskog; Peter Gudmundson; Norman Fleck; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Solid Mechanics; Hållfasthetslära;

    Sammanfattning : This thesis deals with prediction of macroscopic work hardening in a precipitation hardened alloy. The focus is on the particle contribution. A hierarchical modelling approach is adopted where work hardening in a representative material volume on the microscale is homogenized and used to represent the macroscopic hardening. LÄS MER