Search for dissertations about: "Lars Lindgren"

Showing result 11 - 15 of 27 swedish dissertations containing the words Lars Lindgren.

  2. 11. Modeling of Cold Pilgering of Stainless Steel Tubes

    Author : Yağız Azizoğlu; Lars-Erik Lindgren; Jonas Edberg; Per Gradin; Luleå tekniska universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Cold pilgering; finite element method; Hållfasthetslära; Solid Mechanics;

    Abstract : Cold pilgering is a complex forming process used to produce seamless tubes in terms of modeling due to the complexity in kinematic of tools, friction condition and material behavior. The process development has mostly been based on simple formulas and costly full-scale tryouts. READ MORE

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

    Author : Bijish Babu; Lars-Erik Lindgren; Jean-Philippe Ponthot; Luleå tekniska universitet; []
    Keywords : 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;

    Abstract : 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. READ MORE

  5. 13. Preventing pressure ulcers by assessment of the microcirculation in tissue exposed to pressure

    Author : Sara Bergstrand; Margareta Lindgren; Anna-Christina Ek; Maria Engström; Lars-Göran Lindberg; Fredrik Huss; Linköpings universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Pressure ulcer; photoplethysmography; laser Doppler flowmetry; non-invasive; tissue blood flow; reactive hyperemia; pressure-induced vasodilation; interface pressure; risk assessment;

    Abstract : The overall aim of this thesis was to combine optical methods into a system with the ability to simultaneously measure blood flow changes at different tissue depths. The goal of such a system was to reveal vascular mechanisms relevant to pressure ulcer etiology under clinically relevant conditions and in relation to the evaluation of pressure-redistribution support surfaces. READ MORE

  6. 14. Microstructure model for Ti-6Al-4V used in simulation of additive manufacturing

    Author : Corinne Charles Murgau; Lars-Erik Lindgren; Niklas Järvstråt; Robert Pederson; Sören Sjöström; Högskolan Väst; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Titanium alloy; Ti-6Al-4V; Welding; Metal deposition; Additive manufacturing; Wire feed; Finite Element Method; Microstructure model; Johnson-Mehl-Avrami- Kolmogorov; Thermally driven; Production Technology; Produktionsteknik; Manufacturing and materials engineering; Produktions- och materialteknik; Material Mechanics;

    Abstract : This thesis is devoted to microstructure modelling of Ti-6Al-4V. The microstructure and the mechanical properties of titanium alloys are highly dependent on the temperature history experienced by the material. The developed microstructure model accounts for thermaldriving forces and is applicable for general temperature histories. READ MORE

  7. 15. Material characterization of AA7075-T651 deformed at different temperatures and strain rates

    Author : Biswajit Dalai; Lars-Erik Lindgren; Paul Åkerström; Marta-Lena Antti; Luleå tekniska universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hållfasthetslära; Solid Mechanics;

    Abstract : In this licentiate thesis, the mechanical response and the microstructure evolution in aluminum alloy (AA) 7075 in its T651 heat treated state have been studied through mechanical tests at varied conditions of strain rate and temperature.First, compression tests were performed on AA7075-T651 samples at room temperature (RT), 100, 200, 300, 400 and 500 °C (melting temperature of AA7075 is ~635 °C) with two comparatively low strain rates of 0. READ MORE