Diverse scaling behavior of the Ni-20Cr alloy

摘要

A study was undertaken to investigate the isothermal oxidation behavior of the Ni-20Cr binary alloy at 750 and 1000 degreesC. The samples were exposed in air for 6 and 50 h. The oxide phases formed on the alloy were alpha-Cr2O3, NiCr2O4 and NiO. Microstructural examination of the alloy perpendicular to the plane of oxidation revealed co-lateral formation of diverse scale configuration at its surface. The thickness of the scale formed on the alloy surface varied from 1.5 to 18 mum. The protection imparted was due mainly to alpha-Cr2O3; however, various regions of the alloy surface constituted predominantly of NiCr2O4. (C) 2002 Elsevier Science B.V. All rights reserved. [References: 24]