CMAS mitigation for TBCs using a novel aluminum-phosphate based overlay coating

Applied Thin Films, Inc. proposes to use and an innovative aluminum phosphate solution based coating material to act as a sacrificial barrier layer to protect zirconia thermal barrier coatings from molten CMAS ingress and attack. The proposed coating material, known as Cerablak™, will ideally prevent any decrease in zirconia TBC lifetime expectancy and insulation efficiency due to CMAS infiltration, with minimal cost impact and a suitable processing route for rapid implementation. The Cerablak™ coatings will function as a sacrificial barrier layer that reacts with CMAS to form products with elevated melting points, preventing them from infiltrating the TBC. The protection offered to the TBC will allow an increase in useful lifetime and retention of TBC effectiveness during the functional lifetime, which will result in increased fuel efficiency and reliability of turbine engine systems, accompanied by reduced maintenance schedules. This technology will benefit military aircraft propulsion systems as well as the commercial aviation marketplace.BENEFITS: The successful Phase I effort will result in proof of concept that Cerablak™ aluminum phosphate can mitigate CMAS effects upon thermal barrier coating materials (TBCs). If Phase I effort is successful, Phase II work will involve further optimization of coating properties for maximum functionality and demonstration of high performance TBCs in simulated high temperature engine environments. Demonstration of CMAS mitigation in Phase II will include useful lifetime (durability) performance of optimized Cerablak™ coated TBCs. A successful Phase II effort will pipeline this technology for rapid insertion into DOD and commercial applications, which will include TBCs for aeropropulsion applications as well as power generation applications. The successful Phase I and II efforts will align well with the Navy program goals of CMAS mitigation that improve turbine engine lifetimes, fuel efficiency, and lower maintenance costs. These achievements will serve as a public benefit to lower the cost of aeropropulsion and promote increased turbine engine power efficiency and reduced emissions levels. ATFI is pursuing a number of commercial opportunities for promotion of Cerablak™ coating materials. Related to the proposed application of CMAS mitigation for turbine engine TBCs, the most prudent strategy is licensing of the technology to a prime turbine engine contractor. TBCs are an integral part of high output heat engine schemes and hence the technology has to be transitioned to an engine equipment manufacturer through an exclusive or non-exclusive licensing agreement. In addition to the licensing revenue, ATFI will generate revenues from the sale of optimized Cerablak™ coating materials to be used for direct application onto turbine engine components during manufacturing or maintenance processes.