Sökning: "SEM"

Visar resultat 21 - 25 av 699 avhandlingar innehållade ordet SEM.

  1. 21. Atmospheric corrosion of zinc-aluminum and copper-based alloys in chloride-rich environments : Microstructure, corrosion initiation, patina evolution and metal release

    Författare :Xian Zhang; Inger Odnevall Wallinder; Christofer Leygraf; Manuel Morcillo; KTH; []
    Nyckelord :atmospheric corrosion; chloride deposition; Zn-Al alloy coatings on steel microstructure; Cu sheet and Cu alloys; microstructure; corrosion initiation; corrosion product evolution; metal release; SEM; IRAS; CRM.; Kemi; Chemistry;

    Sammanfattning : Fundamental understanding of atmospheric corrosion mechanisms requires an in-depth understanding on the dynamic interaction between corrosive constituents and metal/alloy surfaces. This doctoral study comprises field and laboratory investigations that assess atmospheric corrosion and metal release processes for two different groups of alloys exposed in chloride-rich environments. LÄS MER

  3. 22. Microstructure of a cubic boron nitride tool material before and after hard turning

    Författare :Jenny Angseryd; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; EELS; cBN; microstructure; PCBN; adherent layer; EDX; wear; SEM; EFTEM; TEM;

    Sammanfattning : AbstractPolycrystalline cubic boron nitride (PCBN) materials are widely used in turning of hardened steels due to their beneficial mechanical properties like high hardness at elevated temperatures and, compared to diamond, for being more chemically stable towards iron at temperatures typical for turning operations (800-1000˚C). The wear of PCBN tools is influenced by several factors, like machining parameters, different tool geometries and varying composition of PCBN tools as well as workpiece material. LÄS MER

  4. 23. Atmospheric corrosion of the MgAl alloy AM50 in rheocast and high pressure diecast conditions - Influence of Microstructure, CO2 and NaCl

    Författare :Mehrdad Shahabi Navid; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; SEM; MgAl alloy; Atmospheric corrosion; High pressure diecast; XPS; XRD; Rheocast;

    Sammanfattning : The NaCl-induced atmospheric corrosion of the high pressure diecast (HPDC) MgAl alloy AM50 was investigated. Commercially pure (CP) Mg was used as the reference. Two levels of salt; i.e. LÄS MER

  5. 24. Synthesis of Transition Metal Aluminides from Elemental Powder Mixtures

    Författare :Hossein Sina; Materialteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Aluminides; Intermetallics; Powder Metallurgy; Reactive Sintering; Combustion Synthesis; Thermal Analysis; DSC; Onset temperature; Phase evolution; SEM; EDS; XRD;

    Sammanfattning : Structural components such as those used in gas turbines for energy conversion applications, are subjected to high loads at elevated temperatures. In order to ensure that the components survive under these conditions for a sufficiently long time, it is imperative to select materials with good high temperature properties like strength and corrosion resistance. LÄS MER

  7. 25. Corrosion of painted galvanized steel pretreated with Zr-based thin films

    Författare :Konrad Tarka; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HDG; cyclic corrosion test; SEM; EDS; XRD; Atmospheric corrosion;

    Sammanfattning : For decades, phosphating has been considered state of the art for pretreating car bodies in order to promote corrosion resistance and paint adhesion. Although it offers excellent corrosion protection, the phosphating process has drawbacks. LÄS MER