Sökning: "chromia former"

Hittade 5 avhandlingar innehållade orden chromia former.

1. 1. High Temperature Corrosion of Stainless Steels in Low Oxygen Activity Environments -The effect of H2 and H2O

   Författare :Hamed Hoseini Hooshyar; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; pre-oxidation; chromia former; H2O; High Temperature Corrosion; alumina former; H2;

   Sammanfattning : Gasification of biomass and waste is promising for reducing the use of fossil fuels. While the operation conditions of superheaters and gas coolers in the gasifier are restricted by gas-side corrosion, scientific investigations are very scarce in this field. LÄS MER

3. 2. 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

4. 3. Metallic materials in Solid Oxide Fuel Cells: Oxidation and chromium evaporation properties

   Författare :Mareddy Reddy; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Interconnect; SOFC; High temperature corrosion; Balance of Plant; Chromium evaporation;

   Sammanfattning : Solid oxide fuel cells (SOFCs) are high-temperature energy conversion devices which have great potential due to their high efficiency, low operating costs and flexibility in using conventional hydrocarbon based fuels. However, system cost, durability and performance stability in long-term operation are barriers to the widespread commercialization of SOFC technology. LÄS MER

5. 4. High temperature corrosion of some selected stainless steels and Ni-base alloys – an advanced microscopy study

   Författare :Nooshin Mortazavi Seyedeh; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; oxidation; KCl; STEM; high-temperature materials; STEM EDX; TKD.;

   Sammanfattning : The thesis deals with high temperature corrosion behavior of some selective stainless steels and Ni-base alloys with applications in power generation technologies, e.g. boilers fired by biomass and waste. LÄS MER

7. 5. Ionic Transport in Metal Oxides Studied in situ by Impedance Spectroscopy and Cyclic Voltammetry

   Författare :Johan Öijerholm; Jinshan Pan; Jürgen Fleig; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ionic transport; alumina; zirconia; in situ impedance spectroscopy; molecular dynamics; high temperature cyclic voltammetry; spark plasma sintering; initial oxidation; FeCrAl alloy; grain size; space charge model.; Electrochemistry; Elektrokemi;

   Sammanfattning : Ionic transport in metal oxides is crucial for the functioning of a broad range of different components, such as heat resistant alloys designed for high temperature applications and oxide electrolytes in solid oxide fuel cells. This thesis presents results from in situ electrochemical studies of properties related to ionic transport in metal oxides that are important for their applications as protective oxides and ionic conductors. LÄS MER