Search for dissertations about: "CR"

Showing result 21 - 25 of 504 swedish dissertations containing the word CR.

  2. 21. Study of precipitation in martensitic Fe-C-Cr alloys during tempering : Experiments and modelling

    Author : Ziyong Hou; Joakim Odqvist; Andersson Jörgen; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fe-C-Cr alloy; Microstructure; Precipitates; Tempering of martensite; Electron microscopy; Modelling.; Teknisk materialvetenskap; Materials Science and Engineering;

    Abstract : Understanding the precipitation reaction is very important since precipitation hardening is one of the most effective strengthening mechanisms in metallic alloys. In martensitic steels, a tempering heat treatment is often performed. READ MORE

  4. 22. Laser cladded steel - microstructures and mechanical properties of relevance for railway applications

    Author : Simon Niederhauser; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fe-Cr alloy; Carbon Steel; Microstructure; Internal Stresses; HAZ; Laser Cladding; Co-Cr alloy; Cracking Behaviour; Mechanical Properties; Low Cycle Fatigue;

    Abstract : Owing to increased requirements like increased axle load for railway wheels and rails, new material have to be employed. However, these requirements are mostly surface related, which makes it appropriate to change only the surface layer while keeping the bulk unchanged. READ MORE

  5. 23. Growth and Heat Treatment Studies of Al-Cr-O and Al-Cr-O-N Thin Films

    Author : Ali Khatibi; Lars Hultman; Per Eklund; Marcus Morstein; Linköpings universitet; []
    Keywords : ;

    Abstract : Aluminum oxide based thin films are applied on cutting tool inserts as a top layer to protect the underlying nitride or carbide functional layer from the harsh working environment in terms of abrasive and chemical wear under thermal and pressure load. This Thesis explores the synthesis and characterization of the next generations of multifunctional wear-resistant thin film coatings in the form of Al-Cr-O and Al-Cr-O-N compounds. READ MORE

  6. 24. Development of a new generation of 12% Cr steels: Z-phase strengthened steels

    Author : Masoud Rashidi; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; atom probe tomography; Z-phase; 9-12% Cr steels; martensitic steels; transmission electron microscopy; precipitation hardening; creep;

    Abstract : 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. The thermal efficiency of the steam power plants is limited by the maximum allowed steam temperature and pressure, which in turn are determined by the long-term corrosion and creep resistance of economically viable materials. READ MORE

  7. 25. 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