Research Terms
Researchers at the University of Central Florida and the German Aerospace Center (DLR) have invented a new, non-destructive optical test to identify whether thermal or environmental barrier coatings on components have been infiltrated with particulates, such as dust, sand and ash debris, which can lead to coating failure. Besides detecting particulates, the test also measures the depth of infiltration, so that technicians can evaluate the anticipated lifetime of a coating and the level of damage sustained. The information can thus assist in determining whether a coated part requires a partial or full repair.
Thermal barrier coatings (TBC) help to extend the lifetime of components in high-pressure and high-temperature equipment (turbines, automotive parts, aircraft). Additionally, environmental barrier coatings (EBC) protect parts that are susceptible to water vapor-assisted damage. When equipment treated with such coatings operates under extreme temperatures, calcium, magnesium and aluminum-silicate (CMAS) particles from the equipment’s surroundings can melt and infiltrate the porous structure of the coatings. This can lead to cracking, spalling, and sub-surface delamination that is not easily identified prior to part failure. The ability to detect and locate these defects is crucial to reducing maintenance costs, minimizing downtime, and assuring system safety and reliability. Yet, current methods for analyzing CMAS infiltration and assessing the lifetime of a coated part destroy the component instead of leaving it intact. The invention resolves these issues by using 3D confocal Raman spectroscopy, which provides a non-destructive way to directly measure a CMAS infiltration within a coating, including the depth of infiltration.
The invention is a 3D confocal Raman spectroscopy sensing method that provides a non-destructive technique for characterizing CMAS infiltration and CMAS-assisted damage in TBCs and EBCs. In one example use of the invention, UCF researchers investigated the effects of CMAS infiltration within 7% yttria stabilized zirconia (7YSZ). The test determined the location, composition and concentration of the infiltration based on the phase change initiated by the CMAS within the material. Using 3D-visual output, the test also correlated the results to CMAS infiltration damage. With the ability to determine the composition and location of a CMAS infiltration by detecting a CMAS-induced phase change, the measurement technique could be linked with other existing test measurements to provide definitive correlations between stress and CMAS-affected areas. This measurement can be performed on parts that could then be repaired and replaced or tested within equipment assemblies with portable instrumentation.
Researchers at the University of Central Florida have invented a suite of technologies that allow accurate, remote, real-time temperature measurements of TBCs on components used in extreme operating conditions, such as the blades in turbine engines. The accurate measurement of a coating's temperatures in such environments is crucial to ensure and maintain good performance, the system's functionality, and predictions on the lifetime of the turbine blades. Also, by enabling better monitoring of the thermal parameters in turbine engines, the inventions offer the ability to operate such systems more efficiently and with increased safety.
Following are brief descriptions of the technologies.
Stage of Development
Prototypes available.
Partnering Opportunity
The research team is looking for partners to develop the technology.
Quantifying thermal barrier coating delamination through luminescence modeling, Surface and Coatings Technology, Volume 399, 15 October 2020, 126153. DOI: https://doi.org/10.1016/j.surfcoat.2020.126153
Phosphor
Thermometry Instrumentation for Synchronized Acquisition
of Luminescence Lifetime Decay
on Thermal Barrier Coatings, Measurement
Science and Technology, Volume 31, Issue 5, id.054007, May 2020. DOI: 10.1088/1361-6501/ab64ac
Modeling
luminescence behavior for phosphor thermometry applied to doped thermal barrier
coating configurations in Applied Optics, Vol. 58, Issue 13, pp. D68-D75
(2019), https://doi.org/10.1364/AO.58.000D68
The University of Central Florida invention describes methods for using in-situ resources from the regolith of a celestial body (such as a moon, planet or asteroid) to design and engineer sensors for temperature, damage and pressure. These regolith materials have thermal and optical properties that could enable noncomplex, additive manufacturing of vital components during space missions.
Partnering Opportunity
The research team is seeking partners for licensing and/or research collaboration.
Stage of Development
Prototype available.