Residual Stress in Oxide on NiCrAlY Coating Evaluated by Photoluminescence Spectroscope

Abstract:

The purpose of this study was to understand the effects of thermal exposure temperature on residual stress in thermal grown oxide (TGO) on NiCrAlY coating. The residual stresses in the TGO layer were measured by photo-stimulated luminescence spectrum. High velocity oxygen fuel sprayed (HVOF) method was used to fabricate NiCrAlY coating material. The thermal exposure tests were conducted in air at 900°C, 1000°C, 1100°C for up to 1000 hours using an electric furnace. It was shown that the thickness of the TGO increases with an increase in thermal exposure time with a parabolic curve. The residual stress in the TGO layer increases in thermal exposure time up to 75 hours, and then, the residual stress in the TGO layer decreases slowly. The effects of surface roughness on the residual stress in the TGO were discussed based on experimental results and analysis.

• Periodical: Materials Science Forum (Volume 750)
• Pages: 27-30
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.750.27
• Online since: March 2013
• Authors: Hai Qiang Wang, Takeshi Osaki, Yukiko Nakahara, Shijie Zhu
• Keywords: High Velocity Oxy-Fuel Spraying, Residual Stress, Thermal Barrier Coating (TBC), Thermal Grown Oxide (TGO)

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