Sökning: "atom probe tomography"

Visar resultat 21 - 25 av 45 avhandlingar innehållade orden atom probe tomography.

  1. 21. Oxygen Induced High Temperature Crack Growth in Ni-base Superalloys

    Författare :Leif Viskari; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Diffusion; Environmental influence; Crack growth; Atom probe tomography; Electron Microscopy; Deformation; Crack tip oxidation; Hold-time fatigue;

    Sammanfattning : Oxygen induced crack growth is a serious concern for the performance of Ni-base superalloys. These alloys are used in gas-turbine engines where they are exposed to hightemperatures, mechanical loads and oxygen-rich environments. LÄS MER

  3. 22. High-resolution characterization of TiN diffusion barrier layers

    Författare :Marlene Mühlbacher; Lars Hultman; Christian Mitterer; Lars Johnson; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Diffusion; TiN; Microstructure; Transmission electron microscopy; TEM; Atom probe tomography; APT;

    Sammanfattning : Titanium nitride (TiN) films are widely applied as diffusion barrier layers in microelectronic devices. The continued miniaturization of such devices not only poses new challenges to material systems design, but also puts high demands on characterization techniques. LÄS MER

  4. 23. Development of a new generation of creep resistant 12% chromium steels: Microstructure of Z-phase strengthened steels

    Författare :Masoud Rashidi; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; phase transformation; CrNbN; impact toughness; Creep; CrTaN; Laves-phase; atom probe tomography; precipitation hardening; M2N; MX; transmission electron microscopy; coarsening;

    Sammanfattning : Fossil-fuel fired steam power plants provide more than 60% of the electricity generated worldwide, and account for about one third of the global CO2 emissions. Increasing the steam temperature and pressure leads to a higher thermal efficiency of the power plants and thus lower emissions. LÄS MER

  5. 24. Carbides in martensitic medium carbon low alloyed tool steels studied with small angle scattering techniques, electron microscopy and atom probe tomography

    Författare :Erik Claesson; Peter Hedström; Hans Magnusson; Erik Offerman; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Low alloyed tool steel; Martensite; Small angle scattering; Scanning transmission electron microscopy; Energy dispersive x-ray spectroscopy; atom probe tomography; Scanning precession electron diffraction; Precipitation; carbides; Tempering.; Materials Science and Engineering; Teknisk materialvetenskap;

    Sammanfattning : Medium carbon low alloyed tool steels are used today in various areas to shape plastics, nonferrous metals, and steels, and they are crucial in the manufacturing industry. To be effective, tool steels must be strong and tough, and have high wear resistance and temperature stability. LÄS MER

  7. 25. Precipitate stability in creep resistant 9-12% chromium steels

    Författare :Ardeshir Golpayegani; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; growth; precipitates; coarsening; atom probe field ion microscopy APFIM ; energy filtered TEM EFTEM ; 9-12% chromium steel;

    Sammanfattning : 9-12% chromium steels are used extensively in modern steam power plants at service temperatures up to 600°C. These materials are subjected to creep deformation during exposure which is the limiting factor in increasing the steam temperature and thus the thermal efficiency of the plants. LÄS MER