ISSN:
1573-4889
Keywords:
OXIDATION
;
γ-TiAl INTERMETALLIC
;
ELECTRODEPOSITEDNi-La2O3
;
COMPOSITE FILM
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract A coating of nickel withLa2O3 particles waselectrodeposited on the surface of γ-TiAl toimprove its high-temperature oxidation resistance. Theexperimental results showed that contrary to theoxidation of bare specimens, the electrodepositedNi-La2O3 composite-coated onesexhibited much better resistance to both isothermal andcyclic oxidation in air at 1000 and 900°C. For theoxidation of the Ni-La2O3 composite-coated γ-TiAl EPMA/EDX microanalyses revealed that after the composite film had beenthoroughly oxidized, a La2O3-richNiO layer close to the gas-scale interface and twoalumina-rich layers, with one beneath the NiO layer and the otheradjacent to the γ-TiAl matrix, were produced inthe scale. The results indicated that the preferentiallyformed La2O3-doped NiO layerretarded the growth of rutile and favored the formation of twoalumina-rich layers. The mechanism of the effect of theelectrodeposited Ni-La2O3composite on the oxidation behavior of γ-TiAl isdiscussed in detail.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1018826824364
Permalink
