High-Temperature Oxidation Resistance Behavior Of Porous Ni-16cr-9al Materials

The oxidation behavior of porous Ni-16Cr-9Al alloys at 800 and 1000 degrees C was studied using the isothermal temperature oxidation method. The differences in surface morphology, phase and pore structure between oxidized and non-oxidized materials were characterized by means of scanning electron microscopy, X-ray diffraction analysis and mercury intrusion porosimetry. The results revealed that the oxidation rate of the samples which were oxidized for 420 h at 800 degrees C was 0.012 %(2) h(-1) and the oxidation products were Al2O3 and Cr2O3. The oxidation rate of the samples which were oxidized for 390 h at 1 000 degrees C was 0.415 %(2) h(-1) and the oxidation products were Al2O3, Cr2O3 and Ni(Cr, Al)(2)O-4. All the oxidation kinetics curves obeyed the parabolic law, exhibiting excellent high temperature oxidation resistance.