Thermal barrier coatings (TBCs) are used to protect expensive components, such as turbine blades and car engine parts, that operate in high-temperature environments from thermal load and chemical damage. Thermal conductivity is a measure of how rapidly a material transports heat and is a key property affecting TBC performance. TBCs have a layered structure and thermal conductivity values of individual layers are challenging to measure.

Thermal conductivity is often derived from measurements of thermal diffusivity, which for homogeneous materials at high temperature is commonly measured using the laser flash technique. Recent work has developed a method to derive the properties of individual materials of a layered sample from laser flash measurements. The uncertainties associated with these values are typically estimated using approximate methods and in practice are often overestimated to produce a “safe” uncertainty for decision-making purposes. The primary supporter of this project has stated a need to:

Thermal conductivity is often derived from measurements of thermal diffusivity, which for homogeneous materials at high temperature is commonly measured using the laser flash technique. Recent work has developed a method to derive the properties of individual materials of a layered sample from laser flash measurements. The uncertainties associated with these values are typically estimated using approximate methods and in practice are often overestimated to produce a “safe” uncertainty for decision-making purposes. The primary supporter of this project has stated a need to:

Thermal conductivity is often derived from measurements of thermal diffusivity, which for homogeneous materials at high temperature is commonly measured using the laser flash technique. Recent work has developed a method to derive the properties of individual materials of a layered sample from laser flash measurements. The uncertainties associated with these values are typically estimated using approximate methods and in practice are often overestimated to produce a “safe” uncertainty for decision-making purposes. The primary supporter of this project has stated a need to:

improve the process of specification of TBCs and assessment of nonconforming coatings, thus reducing waste during manufacture and supporting the development of improved measurement methods for TBCs in future, increase the confidence in decisions made at the design stage, such as choice of thicknesses, thus reducing design time and hence cost, and plan their TBC development programmes and testing campaigns more efficiently, thus reducing time to market for products.

The work in EMRP JRP NEW04 has provided a more rigorous calculation method for uncertainties associated with thermal diffusivities and conductivities of the components of TBCs and has demonstrated this method for a simple layered system. However, it has not applied the method to a real industrial problem. Provision of software and a worked example of the method will enable industrial users to apply the algorithms generated in EMRP JRP NEW04 to their problems without needing expert mathematical knowledge, maximising the ease of take-up.