Multilayer thermal barrier coatings for gasified coal based tvirbine engines

Challenges with thermal barrier coatings (TBC) used in integrated gasification combined cycles (IGCC) for power generation become prominent because these turbines operate under higher moisture conditions than that in natural gas turbines. The composition of these impurities and deposited particles varies and shows significant distribution in quantity. Turbines are derated or operated at lower temperatures to extend service life in such varied environments, resulting in lower turbine efficiency. This requires development of advanced TBCs to ensure turbine sustainability at higher operating conditions. Ongoing research at the Center for Thermal Spray Research at Stony Brook University is addressing these challenges through a multilayer solution enabled via advanced processing. Air born particles ingested into the turbine can cause erosion and large exfoliation resulting in thinning of TBCs. The reduction in TBC thickness causes an increase in bond- coat temperature, which, in turn, accelerates bond coat oxidation leading to TBC failure.