Sökning: "Martensitic transformations"

Visar resultat 1 - 5 av 9 avhandlingar innehållade orden Martensitic transformations.

  1. 1. Martensitic Transformations in Steels : A 3D Phase-field Study

    Författare :Hemantha Kumar Yeddu; John Ågren; Annika Borgenstam; Yunzhi Wang; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; Phase-field method; Martensitic transformations; Plastic de formation; Multi-length scale modeling; Microstructure; Stress states; Steels;

    Sammanfattning : Martensite is considered to be the backbone of the high strength of many commercial steels. Martensite is formed by a rapid diffusionless phase transformation, which has been the subject of extensive research studies for more than a century. LÄS MER

  2. 2. Finite element simulation of transformation plasticity in martensitic transformation

    Författare :Kjell Simonsson; Sören Sjöström; Linköpings universitet; []
    Nyckelord :Phase transformations. transformation plasticity; micromechanical models; martensitic transformation; finite element simulations. thermodynamics; moving interface; mechanical dissipation; TECHNOLOGY; TEKNIKVETENSKAP;

    Sammanfattning : This study is concerned with the simulation of transformation plasticity in martensitic transformation. In the first paper the concept of a transformation plasticity strain is introduced from a phenomenological point of view. LÄS MER

  3. 3. Deformation and martensitic phase transformation in stainless steels

    Författare :Peter Hedström; Luleå tekniska universitet; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Engineering Materials; Materialteknik;

    Sammanfattning : The use of high-energy synchrotron x-rays which has enabled three- dimensional structural characterization from the nano- to the macroscopic scale, and now to the meso-scale, such as individual grains and dislocation structures, is a major scientific advance. This is the first technique with sufficient spatial resolution and penetration power to probe the local structure embedded deep within the material. LÄS MER

  4. 4. Thermal and stress induced gamma to epsilon martensitic transformations in Fe-Mn-Si shape memory alloys

    Författare :Magnus Andersson; KTH; []
    Nyckelord :Fe; Mn; Si; Epsilon martensite; Transformation temperatures; Enthalphy; Stress induced; Magnetic transformation; Néel temperature; Shape memory; TECHNOLOGY; TEKNIKVETENSKAP;

    Sammanfattning : .... LÄS MER

  5. 5. Railway Wheel Flats. Martensite Formation, Residual Stresses, and Crack Propagation

    Författare :Johan Jergeus; Chalmers University of Technology; []
    Nyckelord :sliding contact; metallographic investigation; crack propagation; thermal shock; constitutive modelling; phase transformations; railway wheel flats; full-scale field experiments; transformation plasticity; tread damage; residual stresses; spalling; martensite formation;

    Sammanfattning : A railway wheel flat is a flat spot on the rolling surface of a wheel caused by its unintentional sliding on the rail. The reason for the sliding may be poorly adjusted, frozen or defect brakes, or too high braking forces in relation to the available wheel/rail adhesion. LÄS MER