High temperature oxidation behavior of porous Ni-Cr-Mo-Cu materials

Porous Ni-Cr-Mo-Cu materials were fabricated by the activation reaction sintering method using Ni, Cr, Mo and Cu element powders as raw materials. The high temperature oxidation kinetic property was measured by the static mass gain method. And X-ray diffraction (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscope (XPS), energy dispersive spectroscopy (EDS) and pore size tester were conducted to characterize the surface oxide composition, structure and morphology of porous Ni-Cr-Mo-Cu materials at 600-800 ℃. The experimental results show that the oxidation kinetic of the porous material is pseudo-parabolic type. After oxidation at 800 ℃ for 20 h, the maximum pore size decreases from 13.32 μm to 9.52 μm, the air permeability decreases from 97.8 m3/(m2·kPa·h) to 81.3 m3/(m2·kPa·h), and the air permeability of the porous material only decreases by 16.8%. Furthermore, the high temperature oxidation mechanism of porous Ni-Cr-Mo-Cu materials was also investigated. The surfaces of the porous materials are composed of Cr2O3 and NiO films. Thorough the calculation of oxidation kinetics, the activation energy of the porous materials is 152.18 kJ/mol. © 2022, China Science Publishing & Media Ltd. All right reserved.