Search for dissertations about: "martensite formation"

Showing result 1 - 5 of 29 swedish dissertations containing the words martensite formation.

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

    Author : Johan Jergeus; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; 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;

    Abstract : 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. READ MORE

  4. 2. Modelling and Characterisation of the Martensite Formation in Low Alloyed Carbon Steels

    Author : Jessica Gyhlesten Back; Lars-Erik Lindgren; Göran Engberg; Bevis Hutchinson; Luleå tekniska universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Dilatometry; Hardness; EBSD; Martensite; Austenite; Kurdjumov-Sachs; Phase transformation; Modelling; Material Mechanics; Materialmekanik; Steel Forming and Surface Engineering;

    Abstract : The current work contains experimental and theoretical work about the formation of martensite from the austenitic state of the steel Hardox 450. Simulation of rolling and subsequent quenching of martensitic steel plates requires a model that can account for previous deformation, current stresses and the temperature history, therefore dilatometry experiments were performed, with and without deformation. READ MORE

  5. 3. Martensite formation in railway wheel flats

    Author : Johan Jergeus; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Abstract : .... READ MORE

  6. 4. White Layer Formation during Hard Turning of Through-Hardened Martensitic and Bainitic AISI 52100 Steel

    Author : Seyed Hosseini; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; white layers; residual stresses; phase transformation; dynamic recovery; bainite; dynamic recrystallization; carbide deformation; retained austenite; steel; martensite;

    Abstract : Increased demands for flexible manufacturing lines, shorter cycle times and reduced impact on the environment drives the need for optimization of today’s manufacturing. For machining of hardened steel parts (>45 HRC), grinding has been the obvious choice for many decades. However, hard turning has often been considered as a replacement due to e. READ MORE

  7. 5. Characterization of White Layers induced by Hard Turning of AISI 52100 Steel

    Author : Seyed Hosseini; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; white layer; hard turning; IR-pyrometer; nano-sized grains; martensite; cutting temperature; bainite; cubic boron nitride; residual stress; retained austenite; cutting forces;

    Abstract : Hard turning is a machining process applied to metallic materials with hardness above 45 HRC. The process offers high production flexibility and sustainable manufacturing since it allows performing both rough and finishing machining of complex geometries in one single setup. READ MORE