A mechanical stress testing setup with a custom-built compact furnace and cooling system that mimics extreme operating conditions on turbine engines. (DLR)
Because of the difficulty of monitoring turbine engines in operation, most manufacturers test turbine blades either after flight or rely on simulated tests to give them the data on how the various coatings on the blades are performing. Until now, creating an accurate simulation has been out of reach.

New capabilities allow the influence of temperature, stress, and thermal gradients to be studied together. This enables scientists to view the microstructure and internal strain in both the substrate and thermal barrier coating system during real operating conditions and in real time. Manufacturers of turbine engines for airplanes, automobiles, and electric generation plants could expedite the development of more durable, energy-efficient turbine blades.

Specific operating conditions were identified that caused severe gradients, as well as undesired tensile strains in the coating layers. This previously unknown material behavior will be used to validate simulations of these operating conditions, to ensure safe operating windows are maintained. Furthermore, this information can be used to improve the deposition process during manufacturing, develop new coating materials, and allow for the use of coatings at higher temperatures, which could lead to wider adoption.

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