On the Cr-rich continuous and discontinuous precipitation kinetics in Ni-Cr alloys by microstructural characterization and differential scanning calorimetry analysis

Microstructural dependence of continuous and discontinuous Cr-rich precipitation kinetics in Ni-45%Cr alloys on composition and thermal history was investigated by microstructure characterization and dif-ferential scanning calorimetry (DSC). The results indicated that discontinuous precipitation was favored at low temperatures and high Cr contents, while continuous precipitation was favored at high tempera-tures. Activation energies estimated by Kissinger equation using DSC and microstructural evolution showed that Nb and B suppressed, but Zr promoted discontinuous precipitation. It provided a simple effective method to figure out the effect of additions on precipitation kinetics. (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

The study found that in Ni-45%Cr alloys, discontinuous precipitation is favored at low temperatures and high Cr contents, while continuous precipitation is favored at high temperatures. The activation energies estimated showed that Nb and B suppress, but Zr promotes discontinuous precipitation. This research provides an effective method to understand the effect of additives on precipitation kinetics.