Search for dissertations about: "low temperature creep"

Showing result 1 - 5 of 39 swedish dissertations containing the words low temperature creep.

  2. 1. Oxidation, Creep and Fatigue Synergies in Cast Materials for Exhaust Manifolds

    Author : Shengmei Xiang; Joakim Odqvist; Baohua Zhu; Stefan Jonsson; Johan Ahlström; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fatigue; low-cycle fatigue; fatigue in an inert atmosphere; fatigue in a synthetic diesel exhaust atmosphere; corrosion-fatigue; creep-fatigue; high-temperature corrosion; high-temperature fatigue; synergistic effect; corrosion-fatigue synergy; creep-fatigue synergy; high-temperature alloys; fatigue damage; creep-fatigue damage; corrosion-fatigue damage; ductile cast iron; high-alloyed austenitic cast steel; thermal cycling; precipitation; aging.; Teknisk materialvetenskap; Materials Science and Engineering;

    Abstract : The future development of engines of heavy-duty vehicles towards reduced CO2 emission will increase the exhaust gas temperature and render the exhaust atmosphere more corrosive. The current service material of exhaust gas components - a ferritic ductile cast iron called SiMo51 - will soon meet its upper-temperature limit. READ MORE

  4. 2. Mechanical Properties of Welds at Creep Activation Temperatures

    Author : Henrik C.M. Andersson-Östling; Rolf Sandström; Kamran Nikbin; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; creep; creep crack propagation; OFHC copper; welds; nuclear waste disposal; creep modeling; Materials science; Teknisk materialvetenskap;

    Abstract : Welds in materials intended for service at temperatures above the creep activation temperature often develop damage before the base metal. The weld is a discontinuity in the material and stresses and strains often accumulate in the weld. Knowledge of the properties of the weld is essential to the safe operation of the component containing the weld. READ MORE

  5. 3. High temperature performance of materials for future power plants

    Author : Junjing He; Pavel Korzhavyi; Rolf Sandström; Stefano Spigarelli; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Austenitic stainless steels; Nickel based superalloys; Low cycle fatigue; Creep-fatigue; Creep cavitation; Grain boundary sliding; Cavity nucleation; Cavity growth; Creep rupture strength; Advanced ultra-supercritical power plants.; Teknisk materialvetenskap; Materials Science and Engineering;

    Abstract : Increasing energy demand leads to two crucial problems for the whole society. One is the economic cost and the other is the pollution of the environment, especially CO2 emissions. Despite efforts to adopt renewable energy sources, fossil fuels will continue to dominate. READ MORE

  6. 4. Influence of waxes on bitumen and asphalt concrete mixture performance

    Author : Ylva Edwards; Ulf Isacsson; Klaus-Werner Damm; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; bitumen; asphalt; additives; wax in bitumen; polyphosphoric acid in bitumen; rheology; IR-spectroscopy; dynamic mechanic analysis DMA ; bending beam rheometer BBR ; literature study; low temperature physical hardening; highway materials; morphology; modified bitumens; temperature susceptibility; low temperature performance; ageing; microscopy; chromatography; Fourier transform infrared spectroscopy; force ductility; conventional binder tests; asphalt performance; tensile strain restrained specimen test TSRST ; Building engineering; Byggnadsteknik;

    Abstract : This doctoral thesis consists of a literature review, presented in two papers, and another six papers describing experimental studies of the influence of different kinds of wax and polyphosporic acid on bitumen and asphalt concrete mixture properties. The literature review should give an extensive description of the field of knowledge concerning wax in bitumen. READ MORE

  7. 5. Mechanical behaviour of a roller bearing steel : Strength differential effect, low temperature creep and propagation of short cracks

    Author : Irene Linares Arregui; Bo Alfredsson; Nils-Gunnar Ohlson; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Abstract : Fatigue cracks in bearings either initiate from the surface or from an inclusion below the rolling contact surface. Then, short cracks start to propagate. Short crack grow at considerably faster rates than long cracks subjected to a nominally equivalent stress intensity factor range. READ MORE