For decades gas turbines have been a reliable source of propulsion for a variety of marine-based vehicles. Since their adoption as the go-to solution for vehicles requiring a higher power density than conventions diesel engines can produce, they have suffered from corrosion of their alloyed components. Long believed to be the primary source of the corrosion, great efforts have been made to reduce the Na2SO4 and CaSO4 contamination in the fuel sources. Despite recent efforts to reduce sulfur content to near zero levels (
Benefit: The primary benefit of the proposed technology is to accelerate the development of materials and material systems that are resistant to CMAS attack and calcium sulfate hot corrosion. Traditional materials development programs are expensive and time consuming with little certainty about the capabilities of the final result. While the thermochemical and thermomechanical interactions between materials and CMAS or calcium sulfate are relatively well understood, the ML models to be developed in this program will link specific material characteristics to the two degradation mechanisms. These characteristics include the alloy/materials type, the chemical composition of the alloy, materials, and/or coatings, corrosion and/or oxidation activity, fatigue, interdiffusion resistance, creep resistance to phase transitions, the coefficient of thermal expansion compatibility, durability, stress, and temperature stability. The ML models will identify how each of these properties are affected by CMAS attack or hot corrosion. MR&D specializes in the design and analysis of materials for extreme environments. As a service-based company, the designs that we develop become the property of our customers. Thus, the MR&D business plan does not envision growth in terms of numbers of fabricated components. Rather, the proposed Phase I program will result in the technology maturation of a modeling tool which can be used by other turbine engine manufacturers or coating researchers (private and government) to gain insight into the variables which have a critical impact on a materials ability to resist CMAS attack and sulfate-induced hot corrosion. properties. The ML model and accompanying infiltration/degradation model will provide the Navy with a means to encourage researchers to develop specific new coating materials without the high cost of a traditional materials development process. Furthermore, the technology and design tools developed in the Phase I and Phase II programs will allow MR&D to expand its client base and offer more capabilities to our existing customers. This technology will be translated to other commercial and government applications to expand the market advanced material machine learning models. Future variations of the tools developed under this program could address a wider range of alloy materials, various TBCs beyond the Phase I scope, and even EBCs for use on more advanced CMC engine components. Rolls Royce has already expressed an interest in the ML model and accompanying infiltration and degradation model. Should this technology prove feasible, a coating development ML model could open the door to additional funding and development work from turbine engine manufacturers.
Keywords: coating materials, coating materials, sulfate induced hot-corrosion, Materials Development, Modeling, Alloys, thermal barrier coatings, Machine Learning, CMAS
