Strains in Thermally Growing Alumina Films Measured in-situ usingSynchrotron X-rays

Conference · Mon Jan 02 04:00:00 EST 2006

OSTI ID:878327

Hou, P Y; Paulikas, A P; Veal, B W

Strains in thermally grown oxides have been measured in-situ, as the oxides develop and evolve. Extensive data have been acquired from oxides grown in air at elevated temperatures on different model alloys that form Al{sub 2}O{sub 3}. Using synchrotron x-rays at the Advanced Photon Source (Beamline 12BM, Argonne National Laboratory), Debye-Scherrer diffraction patterns from the oxidizing specimen were recorded every 5 minutes during oxidation and subsequent cooling. The diffraction patterns were analyzed to determine strains in the oxides, as well as phase changes and the degree of texture. To study a specimen's response to stress perturbation, the oxidizing temperature was quickly cooled from 1100 to 950 C to impose a compressive thermal stress in the scale. This paper describes this new experimental approach and gives examples from oxidized {beta}-NiAl, Fe-20Cr-10Al, Fe-28Al-5Cr and H{sub 2}-annealed Fe-28Al-5Cr (all at. %) alloys to illustrate some current understanding of the development and relaxation of growth stresses in Al{sub 2}O{sub 3}.

• Research Organization: Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
• Sponsoring Organization: USDOE Director. Office of Science. Office of Basic EnergySciences. Materials Science and Engineering Division, Argonne NationalLaboratory
• DOE Contract Number: AC02-05CH11231
• OSTI ID: 878327
• Report Number(s): LBNL--57683; BnR: KC0201020
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
43 PARTICLE ACCELERATORS
ADVANCED PHOTON SOURCE
AIR
ALLOYS
CORROSION
DIFFRACTION
OXIDATION
OXIDES
RELAXATION
STRAINS
STRESSES
SYNCHROTRONS
TEXTURE