Sökning: "quantitative metallography"

Hittade 5 avhandlingar innehållade orden quantitative metallography.

  1. 1. Precipitation Reactions at High Temperatures in 9-12% Chromium Steels

    Författare :Mats Hättestrand; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; thermo-dynamical simulations; creep resistant; 9-12% chromium steel; energy filtered TEM; precipitates; atom probe field ion microscopy; quantitative metallography;

    Sammanfattning : This thesis reports on quantitative investigations of microstructural changes, mainly precipitation reactions, occurring during heat treatment, ageing and creep of 9-12% chromium steels. Several alloys with varying composition have been investigated. LÄS MER

  3. 2. Evolution of Microstructure in Two Austenitic Alloys at High Temperatures

    Författare :Jenny M Erneman; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; N ; Thermo-Calc; Nb C; gamma prime; DICTRA; APFIM; quantitative metallography; AISI 347; Alloy 800; energy filtered TEM; sigma phase;

    Sammanfattning : A niobium stabilised AISI 347 austenitic stainless steel was investigated after static ageing and creep deformation at temperatures between 500°C and 800°C for times up to 88 000 h. Coarse and fine NbX precipitates and also s-phase precipitates were formed in the temperature range 500-700°C. LÄS MER

  4. 3. Inhomogenity in microstructures

    Författare :Jacek Komeda; KTH; []
    Nyckelord :;

    Sammanfattning : The purpose of the present thesis is to quantitativelycharacterise structural features which contribute to thematerial anisotropy and to relate developed parameters to thematerial properties. Various forms of structural inhomogeneitywere quantified with the help of comuterised image analysisusing quantitative metallography and statistical analysismethods. LÄS MER

  5. 4. Low Temperature Austenite Decomposition in Carbon Steels

    Författare :Albin Stormvinter; Annika Borgenstam; John Ågren; Peter Hedström; John G. Speer; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Carbon steels; Electron backscattered diffraction; Martensite; Microscopy; Microstructure; Thermodynamic modeling;

    Sammanfattning : Martensitic steels have become very important engineering materials in modern society. Crucial parts of everyday products are made of martensitic steels, from surgical needles and razor blades to car components and large-scale excavators. LÄS MER

  7. 5. High temperature performance of materials for future power plants

    Författare :Junjing He; Pavel Korzhavyi; Rolf Sandström; Stefano Spigarelli; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Austenitic stainless steels; Nickel based superalloys; Low cycle fatigue; Creep-fatigue; Creep cavitation; Grain boundary sliding; Cavity nucleation; Cavity growth; Creep rupture strength; Advanced ultra-supercritical power plants.; Teknisk materialvetenskap; Materials Science and Engineering;

    Sammanfattning : Increasing energy demand leads to two crucial problems for the whole society. One is the economic cost and the other is the pollution of the environment, especially CO2 emissions. Despite efforts to adopt renewable energy sources, fossil fuels will continue to dominate. LÄS MER