High-temperature properties for Co-Ni-Al alloys with the γ+β dual phases

This study provides theoretical support for the development of high-temperature structural materials. This study investigates the influence of electronic parameters ( Bo-Md ) on the hardness performance and high-temperature oxidation resistance of nine Co-Ni-Al alloys at different elevated temperatures. By adjusting the composition of Co-Ni-Al alloys, the hardness variations at 298 K, 573 K, 873 K, and 1173 K were examined, with a particular focus on the correlation between Bot-Mdt electronic parameters and alloy hardness. Additionally, a high-temperature oxidation experiment was conducted at 1173 K for 540 ks to evaluate the effect of electronic parameters on oxide layer formation, oxidation rate, and microstructural evolution after oxidation. The results indicate that Bot-Mdt electronic parameters play a crucial role in determining the high-temperature hardness and oxidation resistance of Co-Ni-Al alloys, significantly enhancing high-temperature hardness stability and optimizing oxidation resistance. Furthermore, the study confirms that the d -electron theory effectively guides the compositional design of Co-Ni-Al high-temperature alloys, enabling improvements in both performance and oxidation resistance, thereby providing theoretical support for the development of high-temperature structural materials.