中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
Vol. 17 Special 1 November 2007 |
(1. College of Applied Chemistry, Shenyang Institute of Chemical Technology, Shenyang 110142, China;
2. State Key Laboratory for Corrosion and Protection, Institute of Metal Research,
Chinese Academy of Sciences, Shenyang 110016, China)
Abstract:The oxidation of the Ni-10Cr-xAl(x=7%, 10%, molar fraction) alloys was studied at 1 100 ℃ under 0.1 MPa O2 and compared with that of the binary Ni-7Al and Ni-10Al alloys. The results show that the binary alloys form NiO external scales associated with an internal oxidation of Al. On the contrary, the ternary Ni-10Cr-7Al and Ni-10Cr-10Al form external alumina scale in contact with the alloy substrate. An addition of 10%Cr(molar fraction) into Ni-7Al and Ni-10Al inhibits the internal oxidation of aluminum and considerably reduces the critical content of Al needed to form exclusive alumina scales with respect to binary Ni-Al alloy, providing an example of third-element effect.
Key words: Ni-10Cr-xAl alloy; oxidation; third-element effect