Sökning: "surface composition"

Visar resultat 1 - 5 av 946 avhandlingar innehållade orden surface composition.

  1. 1. ROLE OF SURFACE OXIDES IN SINTERING OF CHROMIUM-ALLOYED STEEL POWDER

    Författare :Henrik Karlsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; water atomisation; surface analysis; sintering; chromium-alloyed steel.; Powder metallurgy; surface reactions; surface; surface oxide; SEM; XRD; AES; XPS;

    Sammanfattning : During water-atomisation and handling of steel powder the surface inevitably oxidises. The surface bound oxide is an important factor in the processing of powder metallurgical (PM) steels, especially in case the powder contains elements forming stable oxides, such as Cr, Mn, and Si. LÄS MER

  3. 2. Localised corrosion and atmospheric corrosion of stainless steels

    Författare :Sukanya Hägg Mameng; Rachel Pettersson; Christopher Leygraf; Thomas Ladwein; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; stainless steel; localised corrosion; atmospheric corrosion; alloy composition; surface finish; surface roughness; surface treatment; surface orientation; contamination; chloride; sulphate; temperature; chlorination; exposure conditions.; Kemi; Chemistry;

    Sammanfattning : This research is focused on defining limiting conditions for corrosion of stainless steels. The aim of the first part (Papers I-IV) was to understand the role of alloying level and environmental parameters on localised corrosion in aqueous conditions. LÄS MER

  4. 3. The effect of surface steps and oxides on the catalytic activity on model Pd and Rh catalysts

    Författare :Chu Zhang; Synkrotronljusfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Surface X-ray diffraction SXRD ; X-ray photonelectron spectroscopy; Catalytic activity; Oxide; Single Crystal surface; surface structure; vicinal surface; CO oxidation; stepped surface; Fysicumarkivet A:2018:Zhang;

    Sammanfattning : A catalyst is a substance that can speed up the rate of a chemical reaction without itself being consumed. Catalysts are crucial for chemical production industries, where about 90% of all chemicals are produced using catalysts. LÄS MER

  5. 4. Surface Interactions in Powder Injection Moulding

    Författare :Elisabeth Johansson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; surfactants; powder injection moulding PIM ; rheology; steel powder; surface interactions; XPS; SIMS; adsorption; surface composition;

    Sammanfattning : Powder Injection Moulding (PIM) is an attractive technique for producing complex components in large quantities my means of powder technology. The process includes mixing powder with a suitable binder, usually a thermoplastic polymer. Because of the large attractive forces between small particles the powder can be agglomerated in the binder. LÄS MER

  7. 5. Functionalized Biomaterial Surfaces by Micro- and Nanofabrication

    Författare :Sarunas Petronis; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nanofabrication; surface characterization; surface topography; surface chemical composition; marine biofouling; force-sensing substrates; microfabrication; surface-enhanced Raman spectroscopy; cell-surface interaction; biointerfaces; biomaterials;

    Sammanfattning : In the field of biomaterials, well-defined nano- and micropatterns or features at material surfaces can serve both as models for investigating material-biosystem interactions and as functional features for inducing, hindering or measuring specific bioreactions or biologic responses. Important bioreactions include protein adsorption and conformation, cell attachment and function, and adhesion and function of organized tissues or whole organisms. LÄS MER