Sökning: "Sintering force"

Visar resultat 1 - 5 av 14 avhandlingar innehållade orden Sintering force.

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

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

    Sammanfattning : 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. LÄS MER

  3. 2. Experiments and simulations on the mechanics of ice and snow

    Författare :Hassan Bahaloohoreh; Johan Casselgren; Simon Larsson; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Experiments; Sintering force; Capillar bridge; liquid film; Discrete Element Method; Particles; Experimentell mekanik; Experimental Mechanics;

    Sammanfattning : In this study, experiments and simulations were conducted to investigate ice and snow. The ice sintering force as a function of temperature, pressing force (contact load), contact duration, and particle size during the primary stage of sintering was formulated using experimental methods along with an approximate, semi-analytic, close-form solution. LÄS MER

  4. 3. Liquid phase sintering of W-Ni-Fe composites : liquid penetration, agglomerate separation and tungsten particle growth

    Författare :Anders Eliasson; Hasse Fredriksson; Thomas Gomez-Acebo; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Liquid phase sintering; heavy metal; particle composites; tungsten; penetration; agglomerate separation; particle interaction; parabolic flight; sounding rockets; microgravity; Kirkendall effect; Metallurgical process engineering; Metallurgisk processteknik;

    Sammanfattning : The initial stage of liquid phase sintering, involving liquid penetration, agglomerate separation, particle spreading and growth has been investigated in experiments using tungsten heavy alloys. The particle composites used were produced by hot isostatic pressing (HIP) of pure powder mixtures of W-Ni-Fe-(Co). LÄS MER

  5. 4. On computational modeling of sintering based on homogenization

    Författare :Mikael Öhman; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Computational homogenization; Multiscale; Mixed variational formulations; Incompressibility; FE2; Liquid phase sintering;

    Sammanfattning : Liquid-phase sintering is the process where a precompacted powder, “green body”, is heatedto the point where (a part of) the solid material melts, and the specimen shrinks while keeping(almost) net shape. In the case of hardmetal, the microstructure is defined by WC-Co-particleswith large pores, whereby molten Co represents the liquid phase. LÄS MER

  7. 5. Development of Composition Gradients in Cemented Carbides

    Författare :Robert Frykholm; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; EPMA; DICTRA; functionally graded materials; gradient sintering; diffusion; APFIM; thermodynamic modelling; SEM; surface zones;

    Sammanfattning : This thesis concerns the formation of tough surface zones, depleted of cubic carbo-nitrides, in cemented carbides. Several materials with varied phase compositions, binder phase volume fraction, and carbon content have been investigated. LÄS MER