Microstructural Investigation of the Ferritic GX12CrMoVNbN9-1 (GP91) Cast Steel

Abstract:

The paper presents research on the microstructure of high chromium martensitic GX12CrMoVNbN9-1 (GP91) cast steel. The steel was subject to investigation in the as-cast state, after hardening as well as after quenching and tempering. The microstructure and morphology of precipitates in GP91 cast steel was examined in terms of changes taking place during the technological process. It has been shown that the examined cast steel is characterized by a microstructure of lath martensite (and polygonized ferrite) with numerous precipitates, such as: M3C, M23C6 and MX (NbC, VX) of diverse morphology. Tempered martensite in the cast steel consists of former austenite grains separated by high angle grain boundaries. These grains are subdivided by high angle boundaries into blocks of martensite laths. The dislocation density of the tempered martensite is high (of about 1014 m-2).

• Periodical: Solid State Phenomena (Volume 186)
• Pages: 287-291
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.186.287
• Online since: March 2012
• Authors: Grzegorz Golański, Paweł Wieczorek
• Keywords: High-Chromium Cast Steel, Microstructure, Precipitate, TEM

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