TY - JOUR
T1 - Effect of superalloy substrate and bond coating on TBC lifetime
AU - Pint, B. A.
AU - Haynes, J. A.
AU - Zhang, Y.
PY - 2010/11/25
Y1 - 2010/11/25
N2 - Several different single-crystal superalloys were coated with different bond coatings to study the effect of composition on the cyclic oxidation lifetime of an yttria-stabilized zirconia (YSZ) top coating deposited by electron beam physical vapor deposition from a commercial source. Three different superalloys were coated with a 7μm Pt layer that was diffused into the surface prior to YSZ deposition. One of the superalloys, N5, was coated with a low activity, Pt-modified aluminide coating and Pt-diffusion coatings with 3 and 7μm of Pt. Three coatings of each type were furnace cycled to failure in 1. h. cycles at 1150°C to assess average coating lifetime. The 7μm Pt diffusion coating on N5 had an average YSZ coating lifetime >50% higher than a Pt-modified aluminide coating on N5. Without a YSZ coating, the Pt-modified aluminide coating on N5 showed the typical surface deformation during cycling, however, the deformation was greatly reduced when constrained by the YSZ coating. The 3μm Pt diffusion coating had a similar average lifetime as the Pt-modified aluminide coating but a much wider scatter. The Pt diffusion bond coating on superalloy X4 containing Ti exhibited the shortest YSZ coating lifetime, this alloy-coating combination also showed the worst alumina scale adhesion without a YSZ coating. The third generation superalloy N6 exhibited the longest coating lifetime with a 7μm Pt diffusion coating.
AB - Several different single-crystal superalloys were coated with different bond coatings to study the effect of composition on the cyclic oxidation lifetime of an yttria-stabilized zirconia (YSZ) top coating deposited by electron beam physical vapor deposition from a commercial source. Three different superalloys were coated with a 7μm Pt layer that was diffused into the surface prior to YSZ deposition. One of the superalloys, N5, was coated with a low activity, Pt-modified aluminide coating and Pt-diffusion coatings with 3 and 7μm of Pt. Three coatings of each type were furnace cycled to failure in 1. h. cycles at 1150°C to assess average coating lifetime. The 7μm Pt diffusion coating on N5 had an average YSZ coating lifetime >50% higher than a Pt-modified aluminide coating on N5. Without a YSZ coating, the Pt-modified aluminide coating on N5 showed the typical surface deformation during cycling, however, the deformation was greatly reduced when constrained by the YSZ coating. The 3μm Pt diffusion coating had a similar average lifetime as the Pt-modified aluminide coating but a much wider scatter. The Pt diffusion bond coating on superalloy X4 containing Ti exhibited the shortest YSZ coating lifetime, this alloy-coating combination also showed the worst alumina scale adhesion without a YSZ coating. The third generation superalloy N6 exhibited the longest coating lifetime with a 7μm Pt diffusion coating.
KW - Oxidation
KW - Pt aluminide coating
KW - Pt diffusion coating
KW - Scale adhesion
KW - TBC lifetime
UR - http://www.scopus.com/inward/record.url?scp=78649943701&partnerID=8YFLogxK
U2 - 10.1016/j.surfcoat.2010.08.154
DO - 10.1016/j.surfcoat.2010.08.154
M3 - Article
AN - SCOPUS:78649943701
SN - 0257-8972
VL - 205
SP - 1236
EP - 1240
JO - Surface and Coatings Technology
JF - Surface and Coatings Technology
IS - 5
ER -