Search for dissertations about: "chromium oxidation"

Showing result 1 - 5 of 61 swedish dissertations containing the words chromium oxidation.

2. 1. Investigations on the Oxidation of Iron-chromium and Iron-vanadium Molten Alloys

   Author : Haijuan Wang; Seshadri Seetharaman; Ashok Lahiri; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Oxidation; High-alloy steelmaking; Retention; CO2-O2; Fe-Cr melt; Fe-Cr-C melt; Fe-V melt; Vanadium containing slags; Kinetics; Thermodynamics properties.; Metallurgical process engineering; Metallurgisk processteknik; Materials science; Teknisk materialvetenskap;

   Abstract : With the progress of high alloy steelmaking processes, it is essential to minimize the loss of valuable metals, like chromium and vanadium during the decarburization process, from both economic as well as environmental view points. One unique technique to realize this aim, used in the present work, is the decarburization of high alloy steel grades using oxygen with CO2 in order to reduce the partial pressure of oxygen. READ MORE

4. 2. The Breakdown of the Protective Oxide on 11% Chromium Steel The Influence of Water Vapour and Gaseous KCl

   Author : Karin Segerdahl; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; 11-Cr-steel; flow rate; water vapour; KCl g ; CrO2 OH 2; temperature dependence; oxidation; breakaway corrosion; chromium evaporation;

   Abstract : The first part of this thesis is focused on the influence of water vapour on the oxidation of X20 steel (CrMoV 11 1). Three parameters were investigated; pH... READ MORE

5. 3. High Temperature Corrosion of FeCrAl Alloys: The influence of water vapour and alkali salt

   Author : Niklas Israelsson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; pre-oxidation; FeCrAl; kinetics; high temperature corrosion; KCl; water vapour; alumina; oxidation;

   Abstract : The corrosive environment in biomass- and waste-fired boilers has been known for several years. The traditionally used FeCr and FeNiCr steels show limited performance in the aggressive environment that contains more H2O and alkali salts than traditional fuel. READ MORE

6. 4. Key Aspects of Sintering Powder Metallurgy Steel Prealloyed with Chromium and Manganese

   Author : Ola Bergman; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Manganese; Prealloyed; Sintering; Mechanical properties; Chromium; Spinel oxide; Powder metallurgy; PM steel; Oxide reduction; Residual oxides; Atmosphere;

   Abstract : The powder metallurgy (PM) process is a cost efficient near net-shape technology suitable for sustainable manufacturing of structural steel components. A drawback with the PM technology is the difficulty to use oxidation sensitive alloying elements, such as Cr and Mn. READ MORE

7. 5. Corrosion and Surface Studies of Stainless Steel and Chromium Carbide Thin-Films

   Author : Jonas Högström; Leif Nyholm; Kristina Edström; Patrik Schmutz; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; corrosion; electrochemistry; thin film; stainless steel; passive film; chromium carbide; carbon oxidation; surface; depth profile; XPS; SEM; EQCM; sputtering;

   Abstract : Although the passive films that form on stainless steels have been extensively studied, the concentration depth profiles are not fully understood. Their thinness makes passive films hard to study, but angle-resolved X-ray photoelectron spectroscopy (ARXPS) is a non-destructive technique that can be used to obtain depth information. READ MORE