Search for dissertations about: "HPHT"

Showing result 1 - 5 of 8 swedish dissertations containing the word HPHT.

  2. 1. TiAlN-based Coatings at High Pressures and Temperatures

    Author : Robert Pilemalm; Magnus Odén; Mikael Olsson; Rachid M'Saoubi; Mats Jöesaar; Linköpings universitet; []
    Keywords : Materials science; thin films; coatings; spinodal decomposition; TiAlN; TiZrAlN; HPHT; high pressure high temperature; BELT-press; transmission electron microscopy; x-ray diifraction; microhardness;

    Abstract : TiAlN and TiAlN-based coatings that are used of relevance as protection of cutting tool inserts used in metal machining have been studied. All coatings were deposited by reactive cathodic arc evaporation using industrial scale deposition systems. The metal content of the coatings was varied by using different combinations of compound cathodes. READ MORE

  4. 2. Use of localised techniques to elucidate the influence of process variables on the corrosion of stainless steels

    Author : Nuria Fuertes; Rachel Pettersson; Inger Odnevall; Stuart Lyon; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Stainless steel; corrosion; passive film; thermal oxides; Volta potential; pickling; deformation; cold rolling; AM; SKPFM; SVET; Kemi; Chemistry;

    Abstract : Several factors during steel manufacture and fabrication can alter the passivity and corrosion behaviour of stainless steels. These include alloying, deformation, welding and heat treatments. READ MORE

  5. 3. New Fullerene Materials Obtained in Solution and by High Pressure High Temperature Treatment

    Author : Alexandr Talyzin; B. Sundqvist; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Chemistry; fullerene; solution; high pressure; Raman spectroscopy; polymerisation; XRD; Kemi; Chemistry; Kemi; Inorganic Chemistry; oorganisk kemi;

    Abstract : Crystallization of C60 and C70 from organic solution often leads to the formation of new solvates and other fullerene compounds. In the present thesis, a number of such solvates were obtained and their phase transitions studied using in situ "in solution" techniques. READ MORE

  6. 4. Synthesis and characterization of nanocarbons as reinforced particles in metal composites

    Author : Vicente Benavides; Alberto Vomiero; Frank Mücklich; Olga Chernogorova; Jordi Ibañez Inza; Luleå tekniska universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Nanocarbons; super elastic hard carbon; Fullerenes under pressure; Disordered carbon; Experimentell fysik; Experimental Physics;

    Abstract : In this work, several scientific problems related to high pressure–high temperature (HP–HT) synthesis of new materials using fullerite as a precursor were studied: first, the mechanism of the transformation of C60 crystal into a nano-clustered graphene phase (NGP) at a pressure of 8 GPa; and second, the effect of disorder introduced into C60 crystals by ball milling prior to HP–HT synthesis on the structure and properties of the NGP. A separate set of experiments was devoted to compression of C60 precursor at unexplored before pressure of 25 GPa and elevated temperatures in search for new type of disordered carbon-based materials. READ MORE

  7. 5. Electronic Characterization of CVD Diamond

    Author : Saman Majdi; Carl Hemmingsson; Uppsala universitet; []
    Keywords : TECHNOLOGY; TEKNIKVETENSKAP;

    Abstract : Diamond is a promising material for high-power, high-frequency and hightemperatureelectronics applications, where its outstanding physical propertiescan be fully exploited. It exhibits an extremely high energy gap, veryhigh carrier mobilities, high breakdown field strength, and the highest thermalconductivity of any wide bandgap material. READ MORE