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Visar resultat 1 - 5 av 360 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Design of carbide-based nanocomposite coatings

   Författare :Erik Lewin; Ulf Jansson; Jörg Patscheider; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; chemistry; thin film; dc magnetron sputtering; carbide; nanocomposite; PVD; solid solution; Chemistry; Kemi; Inorganic chemistry; Oorganisk kemi; Inorganic Chemistry; Oorganisk kemi;

   Sammanfattning : In this thesis research on synthesis, microstructure and properties of carbide-based coatings is reported. These coatings are electrically conducting, and can be tailored for high hardness, low friction and wear, along with load-adaptive behaviour. Tailoring these properties is achieved by controlling the relative phase content of the material. LÄS MER

3. 2. Silicon Carbide Microwave Devices

   Författare :Joakim Eriksson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; SBD; high-power microwave devices; Silicon Carbide; diode mixer; wide band gap devices; physical simulations; resistive mixer; microwave devices; MESFET; Schottky diode;

   Sammanfattning : This work deals with silicon carbide (SiC) microwave devices. It treats two devices; the Schottky diode and the metal semiconductor field effect transistor (MESFET). Different MESFET materials, fabrication processes, theoretical models for physical simulation, and device models are presented. LÄS MER

4. 3. Cemented Carbide Sintering : Constitutive Relations and Microstructural Evolution

   Författare :Anders Petersson; KTH; []
   Nyckelord :Cemented carbides; Sintering; Constitutive relations; Microstructure; Densification; Modelling;

   Sammanfattning : Cemented carbides based on tungsten carbide and cobalt arecommonly produced by a powder metallurgy route including liquidphase sintering. The pressed compact densifies to almost halfits volume during sintering due to pore elimination. LÄS MER

5. 4. Synthesis and Characterization of Ternary Carbide Thin Films

   Författare :Ola Wilhelmsson; Ulf Jansson; Michael Stueber; Uppsala universitet; []
   Nyckelord :Chemistry; Thin film; dc magnetron sputtering; tribology; carbide; PVD; MAX-phase; DFT; solid solution; Kemi;

   Sammanfattning : This thesis reports on synthesis, microstructure and properties of binary and ternary carbide thin films deposited by dc magnetron sputtering. These materials are interesting since they exhibit a wide range of useful properties, such as high hardness, resistance to wear and oxidation, and high electrical conductivity. LÄS MER

7. 5. Thermally stable electrical contacts to 6H silicon carbide

   Författare :Nils Lundberg; Mikael Östling; Claude Jaussaud; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; I-V current -voltage ; C-V capacitance-voltage ; rectifying; ohmic; interface; silicide; carbide; epilayer; Schottky barrier height; current rectification ratio CRR ; specific contact resistivity; transmission line model TLM ; contact resistance; transfer length; Electrical Engineering; Elektro- och systemteknik;

   Sammanfattning : Silicon Carbide (SiC) are at present being developed for use in high temperature (≥ 500◦C) and high-power environments under which conventional semiconductors can hardly perform.  Thermally stable electrical contacts are essential to the ability of SiC to function under such extreme conditions. LÄS MER