High-Temperature Oxidation Behavior of a Ni-Cr-W-Al Alloy

A study was conducted to examine the isothermal oxidation behavior of a new Ni-Cr-W-AI alloy in air at 1250°C with different time. Oxidation kinetics was determined from weight-change measurements. The microstructure and composition of the oxide scale were investigated by means of scanning electron microcopy and X-ray diffraction. The results showed that the oxide scales of the alloy were a compact and continuous outer Cr2O3 and NiCr2O4 layer and an inner AI2O3 layer that was in dendrite shape. Oxides scales with good adherence were formed on the surface of the alloy, which made the alloy perform excellent high-temperature oxidation resistance.