Search for dissertations about: "John Ågren"

Showing result 1 - 5 of 24 swedish dissertations containing the words John Ågren.

  1. 1. Low Temperature Austenite Decomposition in Carbon Steels

    Author : Albin Stormvinter; Annika Borgenstam; John Ågren; Peter Hedström; John G. Speer; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Carbon steels; Electron backscattered diffraction; Martensite; Microscopy; Microstructure; Thermodynamic modeling;

    Abstract : Martensitic steels have become very important engineering materials in modern society. Crucial parts of everyday products are made of martensitic steels, from surgical needles and razor blades to car components and large-scale excavators. READ MORE

  2. 2. Simulation of diffusional processes in alloys : techniques and applications

    Author : Henrik Strandlund; John Ågren; John Morral; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Diffusion; Kirkendall effect; Phase transformations; Random walk; Solute drag; Interfacial mobility; Other materials science; Övrig teknisk materialvetenskap;

    Abstract : This thesis concerns computer simulation of diffusional processes in alloys. The main focus is on the development of simulation techniques for diffusion in single-phase domains, but also diffusion controlled phase-transformations and interfacial processes are discussed. READ MORE

  3. 3. Phase-field modeling of surface-energy driven processes

    Author : Klara Asp Grönhagen; John Ågren; Suzana Fries; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; Phase-field method; surface energy; solute drag; solid-state sintering; multicomponent multiphase flow; wetting; liquid-phase sintering; spinodal decomposition; CALPHAD; Materials science; Teknisk materialvetenskap;

    Abstract : Surface energy plays a major role in many phenomena that are important in technological and industrial processes, for example in wetting, grain growth and sintering. In this thesis, such surface-energy driven processes are studied by means of the phase-field method. READ MORE

  4. 4. Modelling phase separation in Fe-Cr alloys : A continuum approach

    Author : Thomas Barkar; John Ågren; Nele Moelans; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; Phase separation; spinodal decomposition; nucleation; diffusion; thermodynamics; kinetics; steel; ferritic;

    Abstract : The formation of Cr-rich and Fe-rich domains upon ageing of an initially homogeneous Fe-Cr alloy at elevated temperatures (300-600 ºC) is commonly referred to as phase separation. The behaviour originates from a miscibility gap in the Fe-Cr phase diagram. READ MORE

  5. 5. Studies of oxide reduction and nitrogen uptake in sintering of chromium-alloyed steel powder

    Author : Ola Bergman; John Ågren; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; powder metallurgy; chromium; pre-alloying; surface oxides; sintering; Materials science; Teknisk materialvetenskap;

    Abstract : The powder metallurgy (PM) process route is very competitive for mass production of structural steel components with complex shape, due to efficient material utilisation, low energy consumption, and short overall production time. The most commonly used alloying elements are the processing friendly metals Cu, Ni and Mo. READ MORE