Sökning: "kth carbides"

Visar resultat 1 - 5 av 55 avhandlingar innehållade orden kth 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. Influence of microstructure on fatigue and ductility properties of tool steels

    Författare :Mats Randelius; Rolf Sandström; Jens Bergström; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Tool steels; fatigue; ductility; carbides; carbide cluster; inclusion; size distribution; modelling; FEM; Metallurgical process engineering; Metallurgisk processteknik;

    Sammanfattning : Fatigue and ductility properties in various tool steels, produced by powder metallurgy, spray forming or conventionally ingot casting, have been analysed experimentally and successfully compared to developed models. The models are able to predict the fatigue limit and cause for fatigue fracture, and strain- and stress-development until fracture during the ductile fracture process respectively. LÄS MER

  5. 4. Modeling the Microstructure Evolution During and After Hot Working in Martensitic Steel

    Författare :Nima Safara Nosar; John Ågren; Göran Engberg; Hans-Olof Andrén; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Modeling; Martensitic steel; Carbides; Carbide size distribution; Carbide volume fraction; Carbide shape factor; Modellering; Martensitiskt stål; karbider; karbidstorleksfördelning; karbidvolymfraktion; karbidformfaktor; Teknisk materialvetenskap; Materials Science and Engineering;

    Sammanfattning : In this study, the goal is to predict the microstructure evolution during and after the hot working of a martensitic stainless steel with 13% chromium using a physically-based model in the form of a MATLAB toolbox. This model is based on dislocation density theory and consists of coupled sets of evolution equations for dislocation, vacancies, recovery, recrystallization, and grain growth. LÄS MER

  7. 5. Aspects of microstructural evolution in chromium steels in high temperature applications

    Författare :Åsa Gustafson; KTH; []
    Nyckelord :Cr-steels; nucleation; coarsening; model; DICTRA; precipitates; carbides; carbo-nitrides; MX; VN; M23C6; TiC; TEM; EFTEM; Curie-temperature;

    Sammanfattning : In this thesis 9-12 % Cr steels, used for high-temperaturecomponents in fossil-fired power plants are considered. Thecreep strength of thees steels depend on their microstructurethat consists of a matrix of tempered lath martensite withdensely distributed precipitates. LÄS MER