Sökning: "Porosity"

Visar resultat 1 - 5 av 356 avhandlingar innehållade ordet Porosity.

  1. 1. Fatigue strength of engineering materials the influence of environment and porosity

    Detta är en avhandling från Stockholm : KTH

    Författare :Jan Linder; Bengt Lindberg; Lennart Josefsson; [2006]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Stainless steel; cast aluminium; hardened steels; fatigue; corrosion; crack propagation; spot weld; porosity; TECHNOLOGY Materials science Other materials science; TEKNIKVETENSKAP Teknisk materialvetenskap Övrig teknisk materialvetenskap;

    Sammanfattning : The objective of this work was to use LEFM in order to assess the detrimental influence of surrounding chloride-containing environments for stainless steels, hardened steel as well as for a cast aluminium alloy. An additional aim was also to use LEFM to assess the influence of porosity on the fatigue properties for different commercial cast aluminium alloys and manufacturing methods. LÄS MER

  2. 2. Laser welding of ultra-high strength steel and a cast magnesium alloy for light-weight design

    Detta är en avhandling från Trollhättan : University West

    Författare :Karl Fahlström; Lars-Erik Svensson; Leif Karlsson; Michael Rethmeier; [2019]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Laser welding; ultra-high strength steel; cast magnesium alloy; light-weight design; automotive industry; distortion; porosity; Production Technology; Produktionsteknik; Manufacturing and materials engineering; Produktions- och materialteknik;

    Sammanfattning : There is a strong industrial need for developing robust and flexible manufacturing methods for future light-weight design. Better performing, environmental friendly vehicles will gain competitive strength from using light weight structures. LÄS MER

  3. 3. Welding of Ti-6Al-4V: Influence of welding process and alloy composition on microstructure and properties

    Detta är en avhandling från Trollhättan : University West

    Författare :Sakari Tolvanen; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fatigue; microstructure; Ti-6Al-4V; porosity; welding; defects;

    Sammanfattning : Titanium alloys are widely used for components in the fan and compressor sections of aeroengines mainly because of their superior strength-to-weight ratio. Large static compressor components can be manufactured by welding together smaller subcomponents, which has potential to provide benefits such as higher buy-to-fly ratio and improved performance of the components. LÄS MER

  4. 4. Analysis of Deformation of Gas Diffusion Layers and the Impact on Performance of PEM Fuel Cells

    Detta är en avhandling från Department of Energy Sciences, Lund University

    Författare :Jiatang Wang; [2017-07]
    Nyckelord :PEM fuel cell; compression ratio; assembly pressure; porosity; deformed GDL; electric resistance; transport phenomena; model; performance; analysis; OpenFOAM;

    Sammanfattning : Proton exchange membrane (PEM) fuel cells have been promoted due to significant breakthroughs in various aspects and increasing public interests. The porous features of the gas diffusion layer (GDL) and the necessary assembly processes generate localized pressure forces on the channel/shoulder structure of the bi-polar plates (BPP). LÄS MER

  5. 5. Influence of Composition and Pore Geometry on Immiscible Fluid Flow through Greensands: Development of Neutron Transmission Methods and Image Analysis

    Detta är en avhandling från Department of Energy Sciences, Lund University

    Författare :Mikael Solymar; [2002]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; pore geometry; image analysis; fluid flow; petrography; greensand; porosity; glauconite; permeability; neutron transmission methods; fluid saturation;

    Sammanfattning : The effect of the mineralogical composition and pore geometry of sediments on the distribution as well as the flow of immiscible fluids are of importance when evaluating petroleum reservoirs. Greensand containing the clay mineral glauconite is a complex reservoir rock type. LÄS MER