Microstructure, oxidation resistance and high-temperature strength of a new class of 3D open‐cell nickel-based foams

The 3D reticulated Ni–Cr–Fe alloy foams with 34–36 wt.% Cr and 20–24 wt.% Fe were synthesized by co-deposition of chromium and iron onto open–cell nickel foams, and then were homogenized to remove concentration gradients. Emphasis was placed on the research on the oxidation resistance behavior of newly developed Ni–Cr–Fe alloy foams with changing alloy composition, and the results were compared with those of Ni-25Cr and bare nickel foams at 800–1000 °C. The room and high-temperature compression behavior of Ni–Cr–Fe alloy foams was also examined, respectively. The results show that the Ni–36Cr–24Fe alloy foam exhibits the best oxidation resistance among the Ni–34Cr–20Fe, Ni–35Cr–22Fe, Ni–25Cr and bare nickel foams after oxidation at 1000 °C for 120 h. As the Cr and Fe contents increase, the yield stress and the plateau stress of the Ni–Cr–Fe alloy foams increase during the room and high-temperature compression tests. Whereas the compressive strength of the Ni–Cr–Fe alloy foams decreases with the increasing temperature at the same strain rate.