The precipitation of NbCxN1−x significantly affects the high-temperature mechanical properties of Nb microalloyed steel. The control of the precipitation behaviour of NbCxN1−x is the key, especially the nucleation and precipitation from Nb solid solution. We explore to use electropulsing to promote the precipitation of NbCxN1−x through thermodynamic model, chemical phase analysis, XRD and TEM. The modelling research show that electropulsing intensity significantly promotes the nucleation of NbCxN1−x in austenite phase. The higher the electropulsing temperature is, the better the promotion effect is. The chemical phase analysis and XRD investigation results show that electropulsing can increase the amount of precipitation of NbCxN1−x by 50% at 950°C compared to the precipitation without electropulsing.
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