skip to main content

SciTech ConnectSciTech Connect

Title: Influence of a Cerium Surface Treatment on the Oxidation Behavior of Cr2O3-Forming Alloys (title on slides varies: Oxidation Behavior of Cerium Surface Treated Chromia Forming Alloys)

Current goals of the U.S. Department of Energy’s Advanced Power Systems Initiatives include coal generation at 60% efficiency, which would require steam temperatures of up to 760°C. This temperature will require the construction of boiler and turbine components from austenitic stainless steels and nickel alloys. Many of the alloys being considered for use are primarily Cr2O3 forming alloys [1-4]. It is well known that the addition of a small amount of reactive elements, such as the rare earths elements Ce, La, and Y, can significantly improve the high temperature oxidation resistance of both iron- and nickel- base alloys. A list of the benefits of the reactive element effect include: (i) slowing scale growth, (ii) enhancing scale adhesion; and (iii) stabilizing Cr2O3 formation at lower Cr levels. The incorporation of the reactive element can be made in the melt or through a surface infusion or surface coating. Surface modifications allow for the concentration of the reactive element at the surface where it can provide the most benefit. This paper will detail a Ce surface treatment developed at NETL that improves the high temperature oxidation resistance of Cr2O3 forming alloys. The treatment consists of painting, dip coating, or spraying the alloy surfacemore » with a slurry containing CeO2 and a halide activator followed by a thermal treatment in a mild (x10-3 Torr) vacuum. During treatment the CeO2 reacts with the alloy to for a thin CrCeO3-type scale on the alloy surface. Upon subsequent oxidation, scale growth occurs at a reduced rate on alloys in the surface treated condition compared to those in the untreated condition.« less
Authors:
; ; ;
Publication Date:
OSTI Identifier:
916963
Report Number(s):
DOE/NETL-IR-2007-236
TRN: US0804396
DOE Contract Number:
None cited
Resource Type:
Conference
Resource Relation:
Conference: 21st Annual Conference on Fossil Energy Materials, Knoxville, TN, Apr. 30-May 1, 2007
Publisher:
Not published - presentation only (PDF of extended abstract and slides is attached)
Research Org:
National Energy Technology Laboratory (NETL), Pittsburgh, PA, and Morgantown, WV
Sponsoring Org:
USDOE - Office of Fossil Energy (FE)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 24 POWER TRANSMISSION AND DISTRIBUTION; ALLOYS; CERIUM; DIP COATING; NICKEL ALLOYS; OXIDATION; POWER SYSTEMS; RARE EARTHS; STAINLESS STEELS; SURFACE COATING; SURFACE TREATMENTS