TY  - JOUR
AU  - Unocic, K. A.
AU  - Bergholz, J.
AU  - Huang, T.
AU  - Naumenko, D.
AU  - Pint, B. A.
AU  - Vaßen, R.
AU  - Quadakkers, W. J.
TI  - High-temperature behavior of oxide dispersion strengthening CoNiCrAlY
JO  - Materials at high temperatures
VL  - 35
IS  - 1-3
SN  - 1878-6413
CY  - Amsterdam [u.a.]
PB  - Elsevier Science
M1  - FZJ-2018-04905
SP  - 108 - 119
PY  - 2018
AB  - To fabricate oxide dispersion strengthened bond coatings, commercial Co–30wt-%Ni–20Cr–8Al–0•4Y powder was milled with 2% additions of Al2O3, Y2O3 or Y2O3 + HfO2. Low-pressure plasma sprayed, free-standing specimens were oxidised in air + 10%H2O at 1100 °C both isothermally (100 h) and in 500, 1−h cycles. Dry air cyclic testing conducted at both ORNL and FZJ showed remarkably similar results. In general, the water vapour addition caused more scale spallation. Two LPPS specimens without oxide additions were tested for comparison. The specimens with 2%Al2O3 addition exhibited the best behaviour as the powder already contained 0•4%Y. Additions of 2%Y2O3 and especially 1%Y2O3 + 1%HfO2 resulted in over-doping as evidenced by high mass gains and the formation of Y- and Hf-rich pegs. Scanning transmission electron microscopy of the isothermal specimens showed no Hf and/or Y segregation to the alumina scale grain boundaries in the over-doped specimens.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000435483900013
DO  - DOI:10.1080/09603409.2017.1389423
UR  - https://juser.fz-juelich.de/record/851205
ER  -