SuperCoat

Increased functional and environmental demands on today's gas turbines require improved thermal barrier coatings (TBCs) with new morphologies/microstructures and/or made of new materials that result in improved engine efficiency and longer lifetime. A 1% increase in
engine efficiency of a medium sized power plant of 300 MW would result in estimated savings of more than $2 M/year in fuel costs and approximately 25 000 t/year reductions in CO2 emissions so that any small improvements bring huge benefits to both end-users and
environment.

This project will explore a new deposition technique, a new feedstock material and a new coating design for thermal protection of gas turbine components exposed to high service temperatures. Yttria stabilized zirconia is extensively used as TBC material due to its
favorable thermal and mechanical properties, but has reached its limits regarding operating temperature. Gadolinium zirconate is a low conductivity, high temperature ceramic and a very promising new TBC material.

This material will be sprayed using the recently introduced suspension plasma spray technique which allows spraying of nano to submicron particles. Multi-layered strain tolerant coatings with a large fraction of small scale porosity will thus be possible to create. It is expected that these coatings will have significantly better thermal and mechanical properties compared to state-of-the-art today. The suspension plasma spray process is also expected to enable creation of high temperature strain tolerant coatings which will enable a replacement of the EB PVD process. This will dramatically reduce the production cost of TBCs.

The main objective of the project is to develop a new generation of SPS TBC systems which exhibit higher thermal efficiency and longer lifetime than the current state-of-the-art. Specific focus will be on single and multilayer systems and their microstructural changes and failure under cyclic thermal loads. The project will further contribute to the development of the already well-established research activity done at University West on coatings for high temperature applications.

The topic of the project will be also an important part of the research activity to be carried out within the coming KK - Research Environment, University West is applying for. The industrial partners in this project are SIEMENS Turbomachinery and GKN Aerospace. This new type of TBC matches the companies' plans very well in strengthening their positions in design and manufacture of gas turbines for land and aero based applications. Close collaboration with the internationally recognised research groups at Forschungszentrum Jülich, Manchester University and Institute of Plasma Physics Prague is also planned.