Journal of Materials Research and Technology (Sep 2023)
Influence of adding Nb on oxidation resistance of hypoeutectic high-chromium cast iron
Abstract
This experiment investigates the effect of Nb on the oxidation resistance of high-chromium cast iron by adding different contents of Nb to high-chromium cast iron. The experimental results show that the oxidation resistance of high-chromium cast iron with the addition of 1 wt% Nb is increased by 43% compared with high-chromium cast iron without the addition of Nb, which may be related to the formation of a large area of weak oxidation area on the surface of high-chromium cast iron. When more than 2.5 wt% Nb is added to high-chromium cast iron, the oxidation resistance of high-chromium cast iron deteriorates significantly due to a large amount of Fe oxide formed around the Nb2O5. However, as the subsequent Nb content continues to increase to 5 wt%, the oxidation resistance of high-chromium cast iron is improved compared to 2.5 wt% Nb because the dispersion of NbC in the matrix decreases.
