Sökning: "α-alumina"

Visar resultat 1 - 5 av 9 avhandlingar innehållade ordet α-alumina.

  1. 1. Ionic transport of α-alumina below 1000°C : an in-situ impedance spectrosocpy study

    Författare :Johan Öijerholm; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materials science; α-alumina; in-situ impedance spectroscopy; molecular dynamics; spark plasma sintering; conductivity; microstructure; Materialvetenskap; Materials science; Teknisk materialvetenskap;

    Sammanfattning : Ionic conductivity of metal oxides is critical for the function of a broad range of different components, such as electrolytes in solid oxide fuel cells and alloys designed for high temperature applications. In both cases the ionic conductivity can be studied by in situ impedance spectroscopy, which is also able to reveal information on the dielectric properties of the metal oxides, and in some cases the influence of their microstructure. LÄS MER

  3. 2. Microstructure and wear mechanisms of textured CVD alumina and titanium carbonitride coatings

    Författare :Siamak Shoja; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Plastic deformation; Texture; TKD; Electron microscopy; Coatings; CVD; TiCN; α-alumina; Wear mechanisms;

    Sammanfattning : The aim of this thesis is to find the reasons behind how the wear performance of hard coatings produced by chemical vapor deposition (CVD) is influenced by their texture, as this is today not fully known. Therefore, differently textured coatings were synthesized, and subsequently analyzed both before and after specially designed machining tests. LÄS MER

  4. 3. Alumina Thin Films : From Computer Calculations to Cutting Tools

    Författare :Erik Wallin; Ulf Helmersson; Patrick Desjardins; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Alumina; thin films; coatings; sputtering; density functional theory; high power impulse magnetron sputtering; HIPIMS; Material physics with surface physics; Materialfysik med ytfysik; Surface engineering; Ytbehandlingsteknik; Surfaces and interfaces; Ytor och mellanytor;

    Sammanfattning : The work presented in this thesis deals with experimental and theoretical studies related to alumina thin films. Alumina, Al2O3, is a polymorphic material utilized in a variety of applications, e.g., in the form of thin films. LÄS MER

  5. 4. Low-temperature growth of alumina

    Författare :Jon M. Andersson; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Physical phenomena related to the growth of alumina, A12O3, are investigated by experiments and ab initio calculations. Alumina is a well studied material with applications in a variety of areas, due to its many beneficial properties. LÄS MER

  7. 5. Controlling the Formation and Stability of Alumina Phases

    Författare :Jon Martin Andersson; Ulf Helmersson; Eric Kay; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; thin films; alumina; magnetron sputtering; phase stability; density functional theory; Material physics with surface physics; Materialfysik med ytfysik;

    Sammanfattning : In this work, physical phenomena related to the growth and phase formation of alumina, Al2O3, are investigated by experiments and computer calculations. Alumina finds applications in a wide variety of areas, due to many beneficial properties and several existing crystalline phases. LÄS MER