Sökning: "Carbides"

Visar resultat 1 - 5 av 176 avhandlingar innehållade ordet Carbides.

  1. 1. Influence of carbides and nitrides on corrosion initiation of advanced alloys : A local probing study

    Författare :Eleonora Bettini; Jinshan Pan; Thomas Ladwein; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; carbides; nitrides; microstructure; CoCrMo alloys; duplex stainless steels; localized corrosion; transpassive dissoluti on; elemental depletion; AFM; TEM; SEM.;

    Sammanfattning : Advanced alloys often present precipitated carbides and nitrides in their microstructure following exposure to elevated temperatures. These secondary phases are usually undesirable, because potentially deleterious for the corrosion and mechanical performances of the material. LÄS MER

  3. 2. Sintering of cemented carbides : experiments and modeling

    Författare :Sven Haglund; KTH; []
    Nyckelord :;

    Sammanfattning : During sintering of cemented carbides large volumetricshrinkage takes place. About half the volume of the originalgreen body is lost during this process. Due to lotal densitydifferentes within the green body undesired shape changes mayalso occur during sintering. LÄS MER

  4. 3. Strength and Stability of Interfaces in Cemented Carbides

    Författare :Mikael Christensen; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; adhesion; segregation; plastic deformation; microstructure; interfaces; electron structure calculations; cermets; sintering; infiltration; cemented carbides; grain boundaries; cutting tools; density-functional theory; hardmetals; WC-Co; wetting;

    Sammanfattning : Cemented carbides are hard composite materials of great technological importance. They are widely used as tool materials in a large variety of applications where the demands on hardness and toughness are high, including e.g.≈mining, turning, cutting, and milling. LÄS MER

  5. 4. Atomistic modeling of interfaces in WC-Co cemented carbides

    Författare :Martin Petisme; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; analytic bond order potentials; weing; WC-Co; grain boundary sliding; grain boundaries; density functional theory; molecular dynamics; interfaces; cemented carbides;

    Sammanfattning : Grain and phase boundaries are crucial in understanding the properties of real materials. In this thesis, interfaces in WC–Co cemented carbide are modeled atomistically using density functional theory (DFT) and analytic interatomic potentials. LÄS MER

  7. 5. Temperature dependent atomic-scale modeling of interfaces in cemented carbides

    Författare :Martin Gren; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; hardmetals; analytical bond order potential; wetting; WC-Co; density functional theory; free energies; interfaces; complexions; cemented carbides; phase diagram;

    Sammanfattning : Material properties can now be calculated directly from first principles using density functional theory (DFT) which has a great predictive power and can, in cases that are difficult to approach experimentally, provide crucial insights on the atomic and electronic level. Such cases include the thermodynamics of interfaces and surfaces which are crucial factors for the structure and macroscopic properties of many materials, where cemented carbides are one example. LÄS MER