Oxidation of {gamma}-TiAl intermetallic coated with electrodeposited nickel-La{sub 2}O{sub 3} composite films

Journal Article · Thu Apr 01 04:00:00 EST 1999 · Oxidation of Metals

DOI:https://doi.org/10.1023/A:1018826824364· OSTI ID:351482

Peng, X; Tang, Z; Li, T; Wu, W ^[1]

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1. Academia Sinica, Shenyang (China)

A coating of nickel with La{sub 2}O{sub 3} particles was electrodeposited on the surface of {gamma}-TiAl to improve its high-temperature oxidation resistance. The experimental results showed that contrary to the oxidation of bare specimens, the electro-deposited Ni-La{sub 2}O{sub 3} composite-coated ones exhibited much better resistance to both isothermal and cyclic oxidation in air at 1000 and 900 C. For the oxidation of the Ni-La{sub 2}O{sub 3} composite-coated {gamma}-TiAl EPMA/EDX microanalyses revealed that after the composite film had been thoroughly oxidized, a La{sub 2}O{sub 3}-rich NiO layer close to the gas-scale interface and two alumina-rich layers, with one beneath the NiO layer and the other adjacent to the {gamma}-TiAl matrix, were produced in the scale. The results indicated that the preferentially formed la{sub 2}O{sub 3}-doped NiO layer retarded the growth of rutile and favored the formation of two alumina-rich layers. The mechanism of the effects of the electrodeposited Ni-La{sub 2}O{sub 3} composite on the oxidation behavior of {gamma}-TiAl is discussed in detail.

• OSTI ID: 351482
• Journal Information: Oxidation of Metals, Journal Name: Oxidation of Metals Journal Issue: 3-4 Vol. 51; ISSN OXMEAF; ISSN 0030-770X
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
INTERMETALLIC COMPOUNDS
LANTHANUM OXIDES
NICKEL
OXIDATION
PROTECTIVE COATINGS
SCALING
TEMPERATURE RANGE 1000-4000 K
TITANIUM ALLOYS