NANOSTRUCTURED THERMAL BARRIER COATING BASED ON FILTERED ARC PLASMA SOURCE ION DEPOSITION

In an attempt to extend turbine engine on-wing time, thermal barrier coatings (TBC) using various application techniques have been developed. High temperatures corrosion due to penetration of chemically active species along the columnar grains of the topcoat limits the durability of TBCs. This results in degradation of the topcoat thermal insulation ceramic layer and accelerated oxidation of the bondcoat. Using our patented Filtered Arc Plasma Source Ion Deposition (FAPSID) technology, graded nanocomposite transition layers will be deposited between TBC bondcoat and topcoat, and nanostructured topcoats to slow high temperature oxidation of the bondcoat and reduce corrosion of the topcoat resulting in improvement of TBC service life in military engine operating environment . The base superalloy will be a CMSX-4 single crystal. The bondcoat will be a Pt-Hf aluminized system. Several FAPSID nanocomposite coatings, simulating the entire TBC stack architecture will be deposited and their evolution examined in thermal cyclic conditions. These coatings will be evaluated as a system with respect to interactions between adjacent layers. In Phase II the full scale TBC coating architecture will be deposited by FAPSID process, including deposition of nanostructured bond coat. This coating will be evaluated in simulated TBC operation with JP8 fuel.