TY - JOUR
T1 - Effect of Metastable Phase Content Controlled by Heat-Treatment on High Temperature Oxidation Performance of Directionally Solidified Ni-Si Hypereutectic Composites
AU - Li, Wei
AU - Cui, Chunjuan
AU - Liang, Zhanpeng
AU - Liu, Wei
AU - Zhao, Zhiqi
AU - Li, Haolin
AU - Su, Haijun
AU - Luo, Lei
N1 - Publisher Copyright:
© Wuhan University of Technology and Springer-Verlag GmbH Germany, Part of Springer Nature 2026.
PY - 2026/6
Y1 - 2026/6
N2 - Different annealing heat treatment processes were performed on Ni-Si hypereutectic composites at the solidification rate of 40 µm/s to eliminate the metastable phase and the best heat treatment process was selected (annealing temperature 1 000 °C, holding time 4 h). The oxidation weight gain and oxide rate, oxide film morphology, and oxidation kinetics of Ni-Si hypereutectic composites were studied. Moreover, the formation mechanism of the oxide film was investigated through a thermodynamic analysis, specifically by calculating the change of Gibbs free energy associated with the oxidation reactions. It is found that the oxide resistance of the Ni-Si hypereutectic composite without metastable phase is better than that of the 67.9% content of the metastable phase. The surface of oxidized film is composed of granular NiO, while the underlying layer of oxidized film is composed of platelet-shaped SiO2 and spinel-like nickel silicate Ni2SiO4. Directionally solidified Ni-Si hypereutectic composites have potential applications in high temperature fields. However, Ni31Si12 metastable phase is inevitably formed due to the non-equilibrium solidification, which makes the overall properties of the material unstable.
AB - Different annealing heat treatment processes were performed on Ni-Si hypereutectic composites at the solidification rate of 40 µm/s to eliminate the metastable phase and the best heat treatment process was selected (annealing temperature 1 000 °C, holding time 4 h). The oxidation weight gain and oxide rate, oxide film morphology, and oxidation kinetics of Ni-Si hypereutectic composites were studied. Moreover, the formation mechanism of the oxide film was investigated through a thermodynamic analysis, specifically by calculating the change of Gibbs free energy associated with the oxidation reactions. It is found that the oxide resistance of the Ni-Si hypereutectic composite without metastable phase is better than that of the 67.9% content of the metastable phase. The surface of oxidized film is composed of granular NiO, while the underlying layer of oxidized film is composed of platelet-shaped SiO2 and spinel-like nickel silicate Ni2SiO4. Directionally solidified Ni-Si hypereutectic composites have potential applications in high temperature fields. However, Ni31Si12 metastable phase is inevitably formed due to the non-equilibrium solidification, which makes the overall properties of the material unstable.
KW - Ni-Si hypereutectic composite
KW - annealing heat treatment
KW - directional solidification
KW - high temperature oxidation
KW - metastable phase
UR - https://www.scopus.com/pages/publications/105040350117
U2 - 10.1007/s11595-026-3282-1
DO - 10.1007/s11595-026-3282-1
M3 - 文章
AN - SCOPUS:105040350117
SN - 1000-2413
VL - 41
SP - 639
EP - 649
JO - Journal Wuhan University of Technology, Materials Science Edition
JF - Journal Wuhan University of Technology, Materials Science Edition
IS - 3
ER -