Search for dissertations about: "TEM"

Showing result 16 - 20 of 491 swedish dissertations containing the word TEM.

  1. 16. Nanoscale Characterisation of Barriers to Electron Conduction in ZnO Varistor Materials

    Author : Mattias Elfwing; Peter Lagerlöf; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materials science; ZnO varistor material; TEM; SEM; EBIC; ESEM; electron holography; Materialvetenskap; Materials science; Teknisk materialvetenskap; Solid State Physics; fasta tillståndets fysik;

    Abstract : The work presented in this thesis is concerned with the microstructure of zinc oxide varistor materials used in surge protecting devices. This class of material has been characterised with special emphasis on the functional microstructure and the development of the microstructure during sintering. READ MORE

  2. 17. Aspects of microstructural evolution in chromium steels in high temperature applications

    Author : Åsa Gustafson; KTH; []
    Keywords : Cr-steels; nucleation; coarsening; model; DICTRA; precipitates; carbides; carbo-nitrides; MX; VN; M23C6; TiC; TEM; EFTEM; Curie-temperature;

    Abstract : In this thesis 9-12 % Cr steels, used for high-temperaturecomponents in fossil-fired power plants are considered. Thecreep strength of thees steels depend on their microstructurethat consists of a matrix of tempered lath martensite withdensely distributed precipitates. READ MORE

  3. 18. The role of interfaces in oxide thin films

    Author : Tomas Liljenfors; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; thin film; LSMO; EELS; grain boundary; BSTO; interfaces; LCMO; manganites; BTO; bicrystal; TEM; HRTEM; microstructure;

    Abstract : The role of interfaces in oxide thin films has been investigated from a microstructural point of view. Thin films of manganites and titanates have been investigated by transmission electron microscopy (TEM). READ MORE

  4. 19. Mesoporous Silica Formed with Triblock Copolymers

    Author : Katarina Flodström; Fysikalisk kemi; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Fysikalisk kemi; 1H NMR; TEM; SAXS; in situ; mechanism of formation; cubic Ia3d; cubic Im3m; Mesoporous; synthesis; Pluronic; SBA-16; SBA-15; hexagonal p6mm; synchrotron SAXS; Physical chemistry; amphiphilic polymers; silica;

    Abstract : The formation of highly ordered mesoporous silica materials, using PEO-PPO-PEO amphiphilic triblock copolymers (so-called Pluronics) as structure directing agents, has been studied. The materials are formed through the addition of a silica source to a polymer solution of low concentration (2.5 wt ) under acidic conditions. READ MORE

  5. 20. Microstructure of a cubic boron nitride tool material before and after hard turning

    Author : Jenny Angseryd; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; EELS; cBN; microstructure; PCBN; adherent layer; EDX; wear; SEM; EFTEM; TEM;

    Abstract : AbstractPolycrystalline cubic boron nitride (PCBN) materials are widely used in turning of hardened steels due to their beneficial mechanical properties like high hardness at elevated temperatures and, compared to diamond, for being more chemically stable towards iron at temperatures typical for turning operations (800-1000˚C). The wear of PCBN tools is influenced by several factors, like machining parameters, different tool geometries and varying composition of PCBN tools as well as workpiece material. READ MORE