Sökning: "Keywords: TEM"

Visar resultat 1 - 5 av 12 avhandlingar innehållade orden Keywords: TEM.

  1. 1. A TEM Investigation of Contact between Nanoparticles

    Författare :Yiming Yao; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LACBED; CBED; nanoparticles; interface; adhesion; image simulation; energy filtering; misorientation; contacting; strain field TEM;

    Sammanfattning : Interaction between nanoparticles (1~100nm) provides us with answers to fundamental questions in many important applications e.g. adhesion, friction, and cold welding. The attractive force arises from the reduction of the total free surface and thus the total surface energy due to the formation of a boundary between the contacting particles. LÄS MER

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

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

    Sammanfattning : 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. LÄS MER

  4. 3. Microstructure of a cubic boron nitride tool material before and after hard turning

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

    Sammanfattning : 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. LÄS MER

  5. 4. Control of Defects and Subgrains in Epitaxial Perovskite Thin Films

    Författare :Lars Ryen; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; thin film evolution; La0.70Ba0.30MnO3; epitaxial perovskite films; Keywords: TEM; dielectrics; EELS; SrTiO3; YBa2Cu3O7-x; superconductors; colossal magnetoresistance;

    Sammanfattning : This work concerns the microstructure of epitaxial (001) perovskite thin films, studied by transmission electron microscopy (TEM), in particular high resolution TEM, electron energy-loss spectroscopy (EELS), and energy dispersive x-ray analysis. The perovskites exhibit interesting superconducting, dielectric, and magnetic properties. LÄS MER

  7. 5. Study on the Mechanisms for Corrosion and Hydriding of Zircaloy

    Författare :Magnus Oskarsson; KTH; []
    Nyckelord :Zircaloy; Zirconium alloys; Oxidation; Oxide layer; Pre-Transition; Hydriding; Pre-Hydrided; Hydrides; Lithium Hydroxide LiOH ; Lithiated water; Dissolution; Cross sectional TEM;

    Sammanfattning : This thesis is focused on the mechanisms for corrosion andhydriding of Zircaloy. Special attention is paid tomicrostructural characterisation by cross sectionaltransmission electron microscopy of the oxide layer formed. LÄS MER