The failure of metallic parts due to hydrogen embrittlement has been a constant challenge for many industries for decades, and for NASA in particular. The hydrogen embrittlement problems endemic to industries that require heavy use of hydrogen have been solved in various ways. Most of these solutions involve the careful development of alloys that are less susceptible to hydrogen embrittlement. Unfortunately, these alloys often require a sacrifice of some other highly desired material property, such as strength, hardness, ductility, etc. Coatings have also been attempted. However, these coatings and coating techniques have their own drawbacks, which include ceramic coatings that flake off after only a few use cycles and coating techniques that cannot deposit onto a finished part because they require line of sight during deposition. To better mitigate the very pressing hydrogen embrittlement challenge, Summit Information Solutions, Inc. proposes the use of a mature deposition technique that has not seen much use outside of the microelectronics industry. Summit has successfully demonstrated the thin film encapsulate deposition on dummy substrates of Inconel 718 and A-286 stainless steel. These coatings held up in a hot hydrogen at 1,800 degrees C. Summit will demonstrate that this thin film can be deposited onto pipe/tube structures with the same success. Phase II work will involve pull testing in a hot hydrogen environment following the ASTM G142 test protocol
The immediate application for a hydrogen embrittlement mitigation layer will be the ground test stand infrastructure that at the NASA Stennis Space Center. Additionally, the technology will be applicable to future nuclear thermal propulsion test infrastructure and engine hardware. This will also have wide NASA applications for everything from other traditional hydrogen embrittlement needs to coatings for high reflectivity X-Ray optical coatings.
The proposed technology will be useful for a pipe system that requires internal coating. Biofouling prevention would see a direct benefit. Power generation systems are particularly vulnerable to this biofouling, and it is prohibitively expensive to replace or disassemble these systems to apply a coating treatment. The deposition technology will be directly applicable to these systems.