Sökning: "pearlite"

Visar resultat 16 - 20 av 25 avhandlingar innehållade ordet pearlite.

  1. 16. Formation of Bainite in Steels

    Författare :Jiaqing Yin; Annika Borgenstam; Bevis Hutchinson; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fe-C alloys; Bainitic transformation; Proeutectoid ferrite; Upper bainite; Lower bainite; Morphology; Steels.; Teknisk materialvetenskap; Materials Science and Engineering;

    Sammanfattning : A systematic survey of morphology of bainite and proeutectoid ferrite was carried out in order to validate some old thoughts of bainite transformation mechanism. It is confirmed that there is no morphological evidence supporting a sharp change neither between Widmanstätten ferrite and the ferritic component of upper bainite, nor between upper and lower bainite. LÄS MER

  3. 17. Influence of thermal loading on mechanical properties of railway wheel steels

    Författare :Krste Cvetkovski; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; contact creep.; rolling contact fatigue; martensite tempering; shear deformation; Railway wheel steels; heat treatment; residual stress; rapid heating; low cycle fatigue;

    Sammanfattning : Material integrity and properties of wheels are critical in railway traffic, as wheels fulfil the important function of transferring load and traction from the vehicle to the rail track. Steels with a pearlitic microstructure are commonly used for wheels due to their height strength, low cost and good wear properties. LÄS MER

  4. 18. On Thermal Conductivity and Strength in Compacted Graphite Irons : Influence of Temperature and Microstructure

    Författare :Martin Selin; Ingvar L. Svensson; Attila Diószegi; Steve Dawson; Jönköping University; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Compacted Graphite Iron; Thermal Conductivity; Mechanical Properties; Hardness; Microstructure; Plastic Deformation; Hollomon Equation; Elevated Temperature; Materials science; Teknisk materialvetenskap;

    Sammanfattning : Thermal conductivity, hardness and strength are all highly important material properties, affecting the performance and life expectancy of components operating at elevated temperatures. The main purpose of this work has been to increase the knowledge and understanding concerning how mechanical and physical properties are affected by temperature and microstructure in compacted graphite irons. LÄS MER

  5. 19. 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

  7. 20. Effect of Temperature on Mechanical Properties of Railway Wheel Steels

    Författare :Nikas Dimitrios; Chalmers University of Technology; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materials Science; Materialvetenskap;

    Sammanfattning : One of the most important aspects in railway operation is the interaction between rail and wheel. The contact conditions give rise to wear and damage in both components. Medium carbon steels are used in these components due to their combination of high strength and good wear properties in relation to cost. LÄS MER