| AVS 56th International Symposium & Exhibition | |
| Surface Science | Friday Sessions |
| Session SS1-FrM |
| Session: | Nanoclusters, Organics and Beam Induced Chemistry |
| Presenter: | V. Shutthanandan, Pacific Northwest National Laboratory |
| Authors: | V. Shutthanandan, Pacific Northwest National Laboratory S.V.N.T. Kuchibhatla, Pacific Northwest National Laboratory A.S. Lea, Pacific Northwest National Laboratory Z. Zhu, Pacific Northwest National Laboratory M.H. Engelhard, Pacific Northwest National Laboratory S. Thevuthasan, Pacific Northwest National Laboratory P. Singh, University of Connecticut V. Deodeshmukh, Haynes International, Inc. H. GhezelAyagh, Fuel Cell Energy, Inc. |
| Correspondent: | Click to Email |
A combination of ion beam and electron spectroscopy techniques have been used to precisely understand the initial oxidation of a multicomponent alloy system, Haynes®214®. Surface sensitive nature of these techniques has been rightly exploited to precisely identify different phases formed at different times of oxidation. Haynes® 214® is a high temperature, Ni-Cr-Al-Fe based alloy, widely used in a plethora of applications ranging from “clean firing” of ceramics to the gas turbine industry. Various reports exist in the literature, which describe the long term stability of this alloy under oxidizing environments at temperatures above 900oC. Despite the number of applications and significant interest in this alloy, a clear mechanism of the early stage oxidation has not been documented. An effort is underway to estimate the initial nucleation and growth of oxide scale on this alloy in various environments (such as dry and humid air). A combination of ion and electron based techniques such as Rutherford backscattering spectrometry (RBS), nuclear reaction analysis (NRA), particle induced x-ray emission (PIXE), secondary ion mass spectrometry (SIMS) and Auger electron spectroscopy (AES) and x-ray photoelectron spectroscopy (XPS) were used to measure the initial nucleation of the oxide scale on this alloy. NRA was used to track the oxygen depth profile while PIXE and RBS were used to track the changes in matrix components of the alloy for the formation of oxide scale for as-low-as 1 min of oxidation. Chemical analysis of this early stage of oxidation formation was studied by AES and XPS. Chemical surface mapping obtained from Auger analysis indicated that the initial oxide formed is chromia which is completely dominated by alumina after 7 min of oxidation treatment at 900oC in air. Various merits of this work will be discussed along with possible future scope for using Ion beam techniques for processes such as oxidation of metals, a most widely studied problem.