| Popis: |
The oxidation behavior of Ni−20, −40, −60 and −80wt%Cr alloys was studied at 1373 and 1473K for 14.4ks in O 2 by thermogravimetric analysis, X-ray diffraction and scanning electron microscopy. The weight gain of the alloys increased with increasing time of oxidation. Increasing Cr content tended to increase the weight gain of the alloys. The spalling of surface oxide was observed at the oxide/alloy interface for all the alloys. The surface oxide for Ni-20Cr, Ni-40Cr and Ni-60Cr alloys spalled partially. On the other hand, the spalling of the surface oxide for Ni-80Cr alloy occurred over the entire surface. Oxide phases, morphology of surface oxide and oxidation kinetics will be presented. |
