8YSZ/Y_(3)Al_(5)O_(12):Ce^(3+)光敏复合热障涂层的等温氧化及光谱响应特性

Isothermal Oxidation and Spectral Response Characteristics of 8YSZ/Y_(3)Al_(5)O_(12):Ce^(3+) Photosensitive Composite Thermal Barrier Coating

为了监测热障涂层在氧化过程中陶瓷层内部的残余热应力,制备了Y_(3)Al_(5)O_(12):Ce^(3+)含量不同的8YSZ/Y_(3)Al_(5)O_(12):Ce^(3+)光敏复合热障涂层。研究了Y_(3)Al_(5)O_(12):Ce^(3+)不同含量下8YSZ/Y_(3)Al_(5)O_(12):Ce^(3+)光敏复合热障涂层等温氧化过程的失效机理,阐述了陶瓷层内部残余热应力与Y_(3)Al_(5)O_(12):Ce^(3+)的发射光谱的峰值波长之间的内在响应机制;同时研究了8YSZ/Y_(3)Al_(5)O_(12):Ce^(3+)光敏复合热障涂层陶瓷层发射光谱峰值波长偏移量与氧化时间的关系,并拟合了8YSZ/10%Y_(3)Al_(5)O_(12):Ce^(3+)光敏复合热障涂层等温氧化时间与光谱变化的传感方程。结果表明:1 050℃等温氧化100 h过程中8YSZ/Y_(3)Al_(5)O_(12):Ce^(3+)光敏复合热障涂层失效主要是陶瓷层内部残余热应力导致,且随氧化时间的增加,陶瓷层内部残余热应力增加,Y3Al5O12:Ce3+的发射光谱的峰值波长向短波方向偏移;8YSZ/10%Y_(3)Al_(5)O_(12):Ce^(3+)光敏复合热障涂层发射光谱峰值波长偏移量与氧化时间传感方程为:Δλ=155.785 07·t0.004 15-154.792 58。因此,可以通过发射光谱峰值波长的偏移规律表征氧化过程中陶瓷层内部的残余热应力。

In order to monitor the residual thermal stress in the ceramic layer of thermal barrier coating during the oxidation process,8YSZ/Y_(3)Al_(5)O_(12):Ce^(3+)photosensitive composite thermal barrier coatings with different Y_(3)Al_(5)O_(12):Ce^(3+)content were prepared.The failure mechanism of the isothermal oxidation process of 8YSZ/Y_(3)Al_(5)O_(12):Ce^(3+)photosensitive composite thermal barrier coatings with different Y_(3)Al_(5)O_(12):Ce^(3+)content was studied,and the intrinsic response mechanism between the residual thermal stress inside the ceramic layer and the peak wavelength of the emission spectrum of Y_(3)Al_(5)O_(12):Ce^(3+)was elaborated.In addition,the relationship between peak wavelength offset of the emission spectrum of ceramic layer of 8YSZ/Y_(3)Al_(5)O_(12):Ce^(3+) photosensitive composite thermal barrier coating and oxidation time was studied,and the sensing equation of isothermal oxidation time and spectral change of 8YSZ/10%Y_(3)Al_(5)O_(12):Ce^(3+)photosensitive composite thermal barrier coating was fitted.Results showed that the failure of the 8YSZ/Y_(3)Al_(5)O_(12):Ce^(3+) photosensitive composite thermal barrier coating during the 100 h isothermal oxidation at 1050℃was mainly caused by the residual thermal stress in the ceramic layer,and with the increase of oxidation time,the residu⁃al thermal stress inside the ceramic layer increased,and the peak wavelength of the emission spectrum of Y_(3)Al_(5)O_(12):Ce^(3+)was offset to the short⁃wave direction.Furthermore,the sensing equation of 8YSZ/10%Y_(3)Al_(5)O_(12):Ce^(3+)photosensitive composite thermal barrier coating emission peak wavelength offset and oxidation time wasΔλ=155.78507·t 0.00415-154.79258.Therefore,the residual thermal stress in the ceramic layer during the oxidation process could be characterized by the migration rule of the peak wavelength of the emission spectrum.