Sökning: "Retained austenite"

Visar resultat 6 - 10 av 21 avhandlingar innehållade orden Retained austenite.

  1. 6. Cyclic behaviour of carburized steel

    Författare :Lennart Magnusson; Yngve Bergström; Linköpings universitet; []
    Nyckelord :;

    Sammanfattning : The fatigue properties of carburized low alloyed steel have been investigated. The tests in axial fatigue showed that surface carbon below 0.8% and low amounts of retained austenite are advantageous. In bending fatigue the effects of tempering and of surface condition were studied. LÄS MER

  3. 7. Wear and fatigue properties of isothermally treated high-Si steels

    Författare :Alejandro Leiro; Peter Hedström; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materialteknik; Engineering Materials; Centrumbildning - Centrum för högpresterande stål CHS ; Centre - Centre for High Performance Steel CHS ;

    Sammanfattning : In recent years steels containing Si contents of 1,5% or more have been isothermally transformed in order to obtain a microstructure consisting of bainitic ferrite laths and retained austenite. The refined microstructure and presence of retained austenite has allowed the manufacture of steels with high tensile strength and considerable elongation. LÄS MER

  4. 8. Microstructure analysis of wear and fatigue in austempered high-Si steels

    Författare :Alejandro Leiro; Johan Ahlström; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materialteknik; Engineering Materials; Konstruktionsmaterial; Engineering Materials; Centrumbildning - Centrum för högpresterande stål CHS ; Centre - Centre for High Performance Steel CHS ;

    Sammanfattning : Research on austempering of high-Si steels has increased over the last years due to their attractive combination of strength and toughness. The presence of over 1.5% of silicon prevents the precipitation of cementite during austempering and the resulting microstructure consists of bainitic ferrite and retained austenite. LÄS MER

  5. 9. Computational Materials Design of Medium Mn Steels

    Författare :Fei Huyan; Annika Borgenstam; Peter Hedström; Marcel Somers; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : Medium Mn steels (~ 3–10 mass % Mn), a new category of advanced high strength steels, attracted worldwide research interests recent years due to their excellent mechanical properties and low cost. These steels have fine microstructures and contain large fraction of metastable retained austenite (~ 30 volume %), therefore exhibit excellent strength and elongation. LÄS MER

  7. 10. Effect of austenitising temperature and cooling rate on microstructures of hot-work tool steels

    Författare :María Teresa Coll Ferrari; Leif Karlsson; Hans-Olof Andrén; Högskolan Väst; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Tool steel; Heat Treatment; Austenitising Temperature; Large Tools; Tempering Carbides; Bainitic Microstructures; Production Technology; Produktionsteknik; Manufacturing and materials engineering; Produktions- och materialteknik;

    Sammanfattning : The average size of hot-work tools has gradually increased over the past years.This affects the effective temperature cycle tools experience during hardening,as large dimensions prevent uniform and rapid cooling, and thereby the resulting microstructures and properties. LÄS MER