STP1532: Effects of Austenitizing Temperatures on Primary Structure Transformation in Cast High-Speed Steel of M2 Type Inoculated with Powder Additions of W and TiB2

    Chaus, Alexander S.
    Faculty of Materials Science and Technology in Trnava, Slovak University of Technology in Bratislava,

    Boháčik, Michal
    Faculty of Materials Science and Technology in Trnava, Slovak University of Technology in Bratislava,

    Úradník, Peter
    Faculty of Materials Science and Technology in Trnava, Slovak University of Technology in Bratislava,

    Porubský, Ján
    Faculty of Materials Science and Technology in Trnava, Slovak University of Technology in Bratislava,

    Pages: 17    Published: Apr 2012


    Abstract

    The influence of heat treatment on the microstructure of AISI M2 type high-speed steels modified with powder additions of W and TiB2 was studied. The primary focus was on the effects of austenitizing temperatures on the prior austenite grain size and size distribution, volume fraction, and morphology of the eutectic carbides M2C, M6C, and MC, as well as the character of the secondary precipitation of carbides in the high-speed steels studied. It was shown that austenitizing significantly affects the changes in the chemical composition, morphology, size, and character of distribution of the eutectic carbides in the high-speed steels studied, as well as the volume fraction of retained austenite in the matrix and the prior austenite grain size. These changes in carbides seemed to be induced by a diffusion-induced redistribution of alloying elements between the steel matrix and the carbide phases due to their mutual interaction at high temperatures, which is accompanied by carbide decomposition, coagulation and dissolution and, as a consequence, saturation of the solid solution by alloying elements.

    Keywords:

    high-speed steel, heat treatment, microstructure, carbides


    Paper ID: STP153220120011

    Committee/Subcommittee: D02.L0

    DOI: 10.1520/STP153220120011


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