Sökning: "Dislocation network"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden Dislocation network.

  1. 1. Toward first-principles understanding of carbonitride precipitation in steels

    Författare :Dan Fors; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Steels; Coarsening; Interfaces; Peierls-Nabarro model; Diffusion; Precipitates; Density functional theory; Dislocation network; Misfit; Electronic structure;

    Sammanfattning : The most important and widely used group of metallic alloys is steels, whichare alloys of the element iron together with carbon and usually other elementssuch as B, N, V, Nb and Cr. The strength in these alloys is closely connectedto the distribution of point defects, precipitates and grain boundaries whicheffectively act as obstacles for dislocation migration. LÄS MER

  2. 2. Theoretical studies of boron and transition-metal carbonitride additions in steels

    Författare :Dan Fors; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Electronic structure; Dislocation network; Interfaces; Peierls-Nabarro model; Density functional theory; Steels; Coarsening; Diffusion; Misfit; Precipitates;

    Sammanfattning : Martensitic 9-12%Cr steel alloys are today widely used as critical components in fossil-fired steam power plants with steam temperatures up to 600°C, where sound oxidation resistance and excellent creep strength are required. Their strength and long-term creep resistance are closely connected to the presence and stability of Cr-rich M23C6 (M = Cr, Fe) carbides and densely distributed MX precipitates (M = transition metal, X = C or N), which effectively act as obstacles for dislocation migration. LÄS MER

  3. 3. Evolution of microstructure and nanoscale chemistry of Zircaloy-2-type alloys during nuclear reactor operation

    Författare :Johan Eriksson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Zircaloy-2; Nuclear fuel cladding; Atom probe tomography; Zirconium alloys; Clustering; Dislocation loops; Radiation effects; Boiling water reactor;

    Sammanfattning : Zirconium alloys are used as fuel cladding tubes in nuclear reactors. During reactor operation, these alloys are degraded by corrosion, hydrogen pickup (HPU), and radiation-induced growth, processes influenced by the alloying elements. LÄS MER

  4. 4. As-cast AZ91D Magnesium Alloy Properties- Effect of Microstructure and Temperature

    Författare :Hoda Dini; Anders Jarfors; Nils-Eric Andersson; Uta Klement; Jönköping University; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Magnesium alloys; As-cast; AZ91D; Mechanical properties; Microstructural scale effect; Physical modelling;

    Sammanfattning : Magnesium and magnesium alloys are used in a wide variety of structural applications including automotive, aerospace, hand tools and electronic industries thanks to their light weight, high specific strength, adequate corrosion resistance and good castability. Al and Zn are the primary alloying elements in commercial Mg alloys and commonly used in automotive industries. LÄS MER

  5. 5. Characterization of Nanomaterials for Interconnect and Thermal Management in Electronic Packaging

    Författare :Si Chen; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; heat dissipation; electronic packaging; nanomaterial; characterization; thermal interface material; solder; thermoelectric.; interconnect; through silicon via;

    Sammanfattning : Electronic packaging, protecting the fragile chip from atmosphere and providing the paths for signal transmission as well as heat dissipation, is one of the most important parts in electronic devices. The cost, dimensions, performance, and reliability of an electronic device therefore strongly depend on its packaging structures and materials. LÄS MER