Sökning: "hardened steels"

Visar resultat 6 - 10 av 20 avhandlingar innehållade orden hardened steels.

  1. 6. High Resolution Microanalysis of Creep Resistant 9-12% Chromium Steels

    Författare :Lars Lundin; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; martensitic stainless steel; TEM; modified 12% chromium steel; creep resistant; atom-probe field-ion microscopy;

    Sammanfattning : This thesis deals with detailed studies of the microstructure of 9-12% chromium steels. Three alloys with improved creep resistance have been studied in different stages of heat treatment and after creep testing. Two of them were manufactured using PM/HIP and were of the type 10. LÄS MER

  3. 7. High temperature tribology of high strength boron steel and tool steels

    Författare :Jens Hardell; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Maskinelement; Machine Elements;

    Sammanfattning : There are many tribological interfaces that are exposed to elevated temperatures. Typical examples are the interfaces of various moving assemblies, for examples in aerospace industry, power generation and metalworking processes. LÄS MER

  4. 8. Modelling and characterisation of fracture properties of advanced high strength steels

    Författare :Rickard Östlund; Greger Bergman; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hållfasthetslära; Solid Mechanics; Centrumbildning - Centrum för högpresterande stål CHS ; Centre - Centre for High Performance Steel CHS ;

    Sammanfattning : Growing demands for passenger safety, vehicle performance and fueleconomy is a continuous driving force for the increase in use of advancedhigh strength steels (AHSS) in the automotive industry. Thesesteels area characterised by improved formability and crash worthinesscompared to conventional steel grades. LÄS MER

  5. 9. Hard Turning of Bearing Steels. Controlling residual stress and improving fatigue life

    Författare :Michael Jacobson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; x-ray diffraction; bearing steel; residual stress; fatigue life; cutting conditions; hard turning;

    Sammanfattning : There are many different precision mechanical components such as bearings, fuel injectors, gears and hydraulic components, which are made of hardened steels, and have to be machined to a high degree of precision. Traditionally these components are being ground. LÄS MER

  7. 10. Martensitic Transformation in High Carbon Steels - Martensite Tetragonality and Impact of Cooling Rate

    Författare :Thomas Kohne; Annika Borgenstam; Peter Hedström; Jilt Sietsma; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; High carbon steel; Martensitic transformation; Martensite tetragonality; Fatigue performance; Materials Science and Engineering; Teknisk materialvetenskap;

    Sammanfattning : Case-hardened gears are an essential part of our every day life in their role of power transmission in cars and heavy-duty trucks. The increasing use of low pressure carburizing (LPC) for case-hardening in combination with high pressure gas quenching (HPGQ) for cooling opens new possibilities in the design of heat treatments for improved fatigue performance. LÄS MER