Search for dissertations about: "Peter Hedström"

Showing result 1 - 5 of 18 swedish dissertations containing the words Peter Hedström.

  1. 1. Deformation and martensitic phase transformation in stainless steels

    Author : Peter Hedström; Luleå tekniska universitet; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Engineering Materials; Materialteknik;

    Abstract : The use of high-energy synchrotron x-rays which has enabled three- dimensional structural characterization from the nano- to the macroscopic scale, and now to the meso-scale, such as individual grains and dislocation structures, is a major scientific advance. This is the first technique with sufficient spatial resolution and penetration power to probe the local structure embedded deep within the material. READ MORE

  2. 2. Deformation induced martensitic transformation of metastable stainless steel AISI 301

    Author : Peter Hedström; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Engineering Materials; Materialteknik;

    Abstract : Metastable stainless steels are promising engineering materials demonstrating good corrosion resistance and mechanical properties. Their mechanical properties are however significantly affected by the deformation induced martensitic transformation. READ MORE

  3. 3. Fuel Cells and Biogas

    Author : Lars Hedström; Per Alvfors; Peter Lund; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; air bleed; biogas; carbon dioxide; carbon monoxide; current distribution; dilution; efficiency; energy conversion; energy systems; experimental; fuel cell; fuel cell systems; PEFC; poisoning; reformate; SOFC; Chemical energy engineering; Kemisk energiteknik;

    Abstract : This thesis concerns biogas-operated fuel cells. Fuel cell technology may contribute to more efficient energy use, reduce emissions and also perhaps revolutionize current energy systems. The technology is, however, still immature and has not yet been implemented as dominant in any application or niche market. READ MORE

  4. 4. Climate change impacts on production and dynamics of fish populations

    Author : Per Hedström; Pär Byström; Jan Karlsson; Peter Eklöv; Umeå universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Temperature; terrestrial dissolved organic carbon; light extinction; GPP; recruitment; winter mortality; metabolism; cohort competition; fish production; fish biomass;

    Abstract : Ongoing climate change is predicted to increase water temperatures and export of terrestrial dissolved matter (TDOM) to aquatic ecosystems influencing ecosystem productivity, food web dynamics and production of top consumers. Ecosystem productivity is mainly determined by the rates of primary production (GPP) in turn controlled by nutrients, light availability and temperature, while temperature alone affect vital rates like consumption and metabolic rates and maintenance requirements of consumers. READ MORE

  5. 5. Aspects of Structural Evolution in Cemented Carbide – Carbide Size, Shape and Stability

    Author : Ida Borgh; Joakim Odqvist; Peter Hedström; Annika Borgenstam; Jean-Michel Missiaen; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Cemented carbide; Ti; Zr C; Coarsening; Phase separation; C-activity; initial WC powder size; electron backscattered diffraction; microscopy; X-ray diffraction;

    Abstract : Cemented carbide is a composite material used in applications like cutting tools and rock drilling inserts. The material commonly consists of WC grains embedded in a Co-rich binder phase and the material properties strongly depend on the WC grain size. READ MORE