Microstructure Evolution and Precipitation Behavior in Nb and Nb-Mo Microalloyed Fire-Resistant Steels
نویسندگان
چکیده
Microstructure evolution and precipitation behaviors before after tension at elevated temperature of Nb Nb-Mo microalloyed fire-resistant steels were investigated by scanning electron microscopy transmission microscopy, physical–chemical phase analysis small-angle X-ray scattering. Results showed that the martensite austenite (M/A) islands in a rolled state disappeared tempering, cementite large number nanometer-sized carbide precipitated. Those nanosized particles identified as NbC steel (Nb, Mo)C steel. The amount is nearly equal for two state. However, tempering treatment 600 °C, increased more obviously than steel, indicating Mo promotes Nb. Correspondingly, dissolved was reduced, which results decreased coarsening kinetics compared with
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ژورنال
عنوان ژورنال: Metals
سال: 2023
ISSN: ['2075-4701']
DOI: https://doi.org/10.3390/met13010112