Sökning: "Dislocation strengthening"

Visar resultat 1 - 5 av 16 avhandlingar innehållade orden Dislocation strengthening.

  1. 1. Grain Size and Solid Solution Strengthening in Metals

    Författare :Dilip Chandrasekaran; KTH; []
    Nyckelord :strengthening mechanisms; flow stress; solid solution strengthening; grain size strengthening; micromechanical modelling; AFM; EBSD;

    Sammanfattning : The understanding of the strengthening mechanisms is crucialboth in the development of new materials with improvedmechanical properties and in the development of better materialmodels in the simulation of industrial processes. The aim ofthis work has been to study different strengthening mechanismsfrom a fundamental point of view that enables the developmentof a general model for the flow stress. LÄS MER

  3. 2. Creep modelling of particle strengthened steels

    Författare :Hans Magnusson; Rolf Sandström; Göran Engberg; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Particle strengthening; dislocation climb; ferritic steels; dislocation evolution; creep rate modelling; Materials science; Teknisk materialvetenskap;

    Sammanfattning : Materials to be used in thermal power plants have to resist creep deformation for time periods up to 30 years. The role of alloying elements for creep strength of 9-12% Cr steels is analysed. The creep strength in these steels relies on minor additions of alloying elements. LÄS MER

  4. 3. Creep modelling of particle strengthened steels

    Författare :Hans Magnusson; Rolf Sandström; Wolfgang Blum; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; creep rate modelling; particle hardening; microstructure evolution; dislocation climb; ferritic steels; Materials science; Teknisk materialvetenskap;

    Sammanfattning : Materials used in thermal power plants have to resist creep deformation for time periods up to 30 years. Material evaluation is typically based on creep testing with a maximum duration of a few years. This information is used as input when empirically deriving models for creep. LÄS MER

  5. 4. Mechanism-based flow stress model for Ti-6Al-4V : applicable for simulation of additive manufacturing and machining

    Författare :Bijish Babu; Lars-Erik Lindgren; Jean-Philippe Ponthot; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Material modeling; Ti-6Al-4V; dislocation density; vacancy concentration; additive manufacturing; hot forming; heat treatment; Material Mechanics; Materialmekanik;

    Sammanfattning : Ti-6Al-4V has remarkable properties such as high specific mechanical properties (viz. stiffness, strength, toughness, fatigue resistance), corrosion resistance, biocompatibility etc. These properties make it attractive for applications in aerospace, chemical industry, energy production, surgical implants, etc. LÄS MER

  7. 5. Thermomechanical Processing of Nickel-Base Alloy 825

    Författare :Munir Al-Saadi; Pär Jönsson; Christopher Hulme-Smith; Göran Engberg; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Alloy 825; Cast and wrought structures; Hot compression test; Microstructural evaluation; Modelling; Yield strength; Strengthening mechanisms; Teknisk materialvetenskap; Materials Science and Engineering;

    Sammanfattning : Alloy 825 material was studied using a Gleeble-3800 thermosimulatorby performing single-hot compression experiments.Optical microscopy and electron backscatter diffraction wereutilized to characterize the microstructure. Dynamicrecrystallization is not considerable in the as-cast alloy anddislocation recovery is deemed to be dominant. LÄS MER