Search for dissertations about: "Si3N4"

Showing result 1 - 5 of 30 swedish dissertations containing the word Si3N4.

  1. 1. The Microstructure of Metal Oxide Additive Silicon Nitride Ceramics

    Author : Maria Knutson Wedel; Chalmers University of Technology; []
    Keywords : microstructure; SEM; HIP; TEM; ZrO2; Si3N4;

    Abstract : This work is concerned with Si3N4 ceramics fabricated with different metal oxide additives, viz. Y2O3, Al2O3, ZrO2 and ZrO2(+3 mol% Y2O3), which have been densified by hot isostatic pressing (HIP). READ MORE

  2. 2. Silicon nitride for total hip replacements

    Author : Maria Pettersson; Cecilia Persson; Håkan Engqvist; Staffan Jacobson; Kenneth Holmberg; Uppsala universitet; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; SiNx; Si3N4; coatings; CoCr; Ti; alloy; tribology; wear; corrosion; dissolution; debris; hip; arthroplasty; Teknisk fysik med inriktning mot materialvetenskap; Engineering Science with specialization in Materials Science;

    Abstract : For more than 50 years total hip replacements have been a common and successful procedure to increase patient mobility and quality of life. The 10-year implant survival rate is 97.8%. READ MORE

  3. 3. Spark plasma sintered ZrO2-SiO2 glass ceramics and Si3N4 bioceramics

    Author : Le Fu; Wei Xia; Håkan Engqvist; Jérôme Chevalier; Uppsala universitet; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ZrO2-SiO2 glass ceramic; high-strength; translucency; 3D nano-architecture; Si3N4 bioceramic; biodegradable; spark plasma sintering; Materialvetenskap; Materials Science;

    Abstract : This thesis focuses on elaboration and characterization of two types of bioceramics: one is ZrO2-SiO2 nanocrystalline glass ceramic (NCGC) for dental application. The goal is to develop new ZrO2-SiO2 NCGCs with a combination of high strength and high translucency; the other is biodegradable Si3N4 ceramics for spinal fusion. READ MORE

  4. 4. Spark Plasma Sintering of Si3N4-based Ceramics : Sintering mechanism-Tailoring microstructure-Evaluationg properties

    Author : Hong Peng; Zhijian (James) Shen; Mats Nygren; Michael J. Hoffmann; Stockholms universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; spark plasma sintering; silicon nitride ceramics; grain growth kinetic; superplasiticity; liqiud phase sintering; Chemistry; Kemi;

    Abstract : Spark Plasma Sintering (SPS) is a promising rapid consolidation technique that allows a better understanding and manipulating of sintering kinetics and therefore makes it possible to obtain Si3N4-based ceramics with tailored microstructures, consisting of grains with either equiaxed or elongated morphology. The presence of an extra liquid phase is necessary for forming tough interlocking microstructures in Yb/Y-stabilised α-sialon by HP. READ MORE

  5. 5. Grain Morphology and Intergranular Structure of Si3N4 and Al2O3 Based Ceramics

    Author : Håkan Björklund; Chalmers University of Technology; []
    Keywords : whiskers; stereology; electron microscopy; sintering; silicon nitride; quantitative microscopy; grain growth; ceramics; microstructure; aluminium oxide;

    Abstract : This thesis concerns factors controlling the grain morphology in Si3N4 and Al2O3 based ceramics. The microstructures of the ceramics were characterized by scanning electron microscopy in combination with quantitative microscopy and stereologic methods. READ MORE