Effect of APS flash bond coatings and curvature on TBC performance on rod specimens

SURFACE & COATINGS TECHNOLOGY

卷:378

Article; Proceedings Paper

Lance, M. J.¹  Thiesing, B. P.²  Haynes, J. A.¹  Gildersleeve, E. J.³  Sampath, S.³  Pint, B. A.¹ 

[1] Oak Ridge Natl Lab, 1 Bethel Valley Rd, Oak Ridge, TN 37831 USA

[2] No Arizona Univ, POB 4185, Flagstaff, AZ 86011 USA

[3] SUNY Stony Brook, 100 Nicolls Rd, Stony Brook, NY 11794 USA

关键词: Photo-stimulated luminescence piezospectroscopy (PLPS);    Furnace cycle testing (FCT);    APS flash bond coating;    Alumina scale;    TBC;    HVOF bond coating;    VPS bond coating;   

DOI  :  10.1016/j.surfcoat.2019.124940

来源: Elsevier

【 摘 要 】

The addition of an air plasma sprayed (APS) flash bond coating layer on top of a high velocity oxy-fuel (HVOF) bond coating significantly extended the lifetime of APS yttria stabilized zirconia (YSZ) thermal barrier coatings (TBC) on rod specimens of superalloy 247 tested using 100-h cycles in air +10%H2O at 1100 degrees C. The flash bond coatings of both NiCoCrAlY and NiCoCrAlYHfSi powder were compared to an HVOF-only and a vacuum plasma sprayed (VPS) NiCoCrAlYHfSi bond coating. The flash coatings appear to form a mixed oxide-metal zone, which likely inhibits crack formation and therefore extends lifetime compared to conventional bond coatings. The underlying dense HVOF layer appeared to act as a source of Al for this intermixed zone and prevented the oxide from penetrating deeper into the bond coating. Residual stress in the thermally-grown Al2O2 scale was measured using photo-luminescence piezospectroscopy (PLPS) as a function of time for each coating variation, including a comparison of concave and convex surfaces on a specially designed rod.

【 授权许可】

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