Microstructural and chemical effects in Al sub 2 O sub 3 implanted with iron at room temperature and annealed in oxidizing or reducing atmospheres

Journal Article · Tue Oct 01 04:00:00 EDT 1991 · Journal of Materials Research; (United States)

DOI:https://doi.org/10.1557/JMR.1991.2145· OSTI ID:5162421

McHargue, C J; Sklad, P S; White, C W; Farlow, G C ^[1]; Perez, A ^[2]; Marest, G ^[3]

---

1. Oak Ridge National Laboratory, Oak Ridge, Tennessee (USA)
2. Departement de Physique des Materiaux, Universite Claude Bernard Lyon 1, Villeurbanne Cedex (France)
3. Institut de Physique Nucleaire de Lyon, IN2P3-CNRS, Universite Claude Bernard Lyon 1, Villeurbanne Cedex (France)

Rutherford backscattering (RBS)-ion channeling, transmission electron microscopy (TEM), and conversion electron Moessbauer spectroscopy (CEMS) have been used to determine the structure of {alpha}--Al{sub 2}O{sub 3} implanted with iron at room temperature. Changes produced by post-implantation annealing in oxidizing and reducing atmospheres were followed using the same techniques. Implantation of 160 keV Fe at room temperature produces a damaged but crystalline microstructure for fluences as high as 1{times}10{sup 17} Fe/cm{sup 2}. The iron resides in a variety of local environments: three Fe{sup 2+} components, one Fe{sup 0} component, and two Fe{sup 4+} components. The relative amount of each component varies with implantation fluence. Only the Fe{sup 0} component seems to be associated with second-phase formation. In this case, 2 nm diameter {alpha}-iron particles were detected by TEM studies. Recovery of implantation-induced disorder in the Al- and oxygen-sublattices occurs in two stages for annealing in oxygen and in one continuous stage for hydrogen-annealing. The end state for iron is Fe{sup 3+} for oxygen anneals and Fe{sup 0} for hydrogen anneals. The precipitated phases observed are those to be expected from the equilibrium phase diagrams.

• DOE Contract Number: AC05-84OR21400
• OSTI ID: 5162421
• Journal Information: Journal of Materials Research; (United States), Journal Name: Journal of Materials Research; (United States) Vol. 6:10; ISSN JMREE; ISSN 0884-2914
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360202* -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
ANNEALING
BACKSCATTERING
CHALCOGENIDES
CHANNELING
CHEMICAL REACTIONS
CRYSTAL STRUCTURE
ELASTIC SCATTERING
ELECTRON MICROSCOPY
ELEMENTS
ENERGY RANGE
HEAT TREATMENTS
ION CHANNELING
ION IMPLANTATION
IRON
KEV RANGE
KEV RANGE 100-1000
MEDIUM TEMPERATURE
METALS
MICROSCOPY
MICROSTRUCTURE
MOESSBAUER EFFECT
OXIDATION
OXIDES
OXYGEN COMPOUNDS
REDUCTION
RUTHERFORD SCATTERING
SCATTERING
TRANSITION ELEMENTS
TRANSMISSION ELECTRON MICROSCOPY