Sökning: "nitridation"

Visar resultat 1 - 5 av 22 avhandlingar innehållade ordet nitridation.

  1. 1. High-temperature corrosion properties of chromia- and alumina-forming alloys

    Författare :Tommy Sand; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; High-temperature corrosion; Alumina scale; Chromia scale; Cr-evaporation; Nitridation; Oxidation;

    Sammanfattning : Electricity production, transportation, and manufacturing industry are some of the largest sources of greenhouse gas emissions. In many cases, these processes are carried out at high temperature and energy efficiency is limited by material degradation, so-called ‘high-temperature corrosion’. LÄS MER

  3. 2. Molecular beam epitaxy growth and characterization of GaN, AlN and AlGaN/GaN heterostructures

    Författare :Stefan Davidsson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; two-dimensional electron gas; MBE; Al2< sub>O3< sub>; epitaxial growth; III-nitride; molecular beam epitaxy; GaN; nucleation layer; nitridation; AlGaN; HFET; 2DEG density; AlN; 2DEG; buffer layer; sapphire; 2DEG mobility; heterostructure field effect transistor;

    Sammanfattning : The III-nitride materials, consisting of Al, Ga, In and N, have several physical properties that make them attractive for semiconductor devices in electronic and optic applications. A wide range of direct energy bandgaps (0.7 eV - 6.1 eV) can be obtained. LÄS MER

  4. 3. Novel Insights into the Oxidation of High Temperature Alloys - The Role of Environment, Microstructure and Reactive elements

    Författare :Nooshin Mortazavi Seyedeh; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; reactive elements; nitridation; High temperature materials; nitrides; alumina; hydrides; microstructure; chromia; oxidation;

    Sammanfattning : The properties of materials can be deteriorated, when they react with an environment at high temperature and form various types of corrosion products, such as oxides and nitrides. In order to perform successfully at elevated temperatures, all these materials are required to be protected by a slow-growing, continuous and adherent surface oxide layer. LÄS MER

  5. 4. Nitrogen and Water in High Temperature Corrosion - Insights from First Principle Calculations

    Författare :Vedad Babic; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; DFT; alumina; nitridation; corrosion; chromia; hydrogen;

    Sammanfattning : Service life-time of alloys used in high temperature applications is often limited by corrosion. FeCrAl(Re) alloys are partially designed to form a protective α-alumina oxide scale at elevated  temperatures in order to mitigate further oxidation. LÄS MER

  7. 5. On the preparation and structure of O-sialons

    Författare :Jörgen Sjöberg; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; silicon oxynitride; Sialon; ammonia; crystal structure; nitridation; extended X-ray absorption fine structure; nuclear magnetic resonance; neutron diffraction;

    Sammanfattning : .... LÄS MER