Ceramic Springs

Hypersonic aircraft, especially reusable hypersonic aircraft, require advancements in high temperature materials because of the extreme temperatures resulting from frictional heating. One aspect of this problem is making seals that can function through a very large temperature range, perhaps up to 1000 C or higher. Metallic springs essentially lose their ability to function at 600 C or below. Ceramic springs, principally made of silicon nitride, are capable of functioning throughout that temperature range, but lack the strength required for most applications. They also undergo very limited deformation before failure. TDA will improve the feedstocks and modify the existing process for manufacturing ceramic compression springs. Through improvements to the grain structure, the resulting springs will overcome their previous limitations.

Ceramic compression springs are primarily being developed so that high temperatures seals in the (sc)ramjet engines can be preloaded. However, the high temperature – capable springs could also solve problems in the control surface and/or leading edge thermal protection system. These needs are particularly acute for re-usable hypersonic transports, including the descendants fo the National Aerospace Plane.

There will be many uses for these high temperatures outside of NASA. Most obviously, certain (single-use) air-breathing hypersonic weapon systems have the same needs as NASA. However, the chemical resistance and high temperature stability of ceramic springs will allownew sealing options in a wide variety of industrial processes. Ceramic springs that allow seals to be made between smaller, simpler pieces of tooling can cut manufacturing costs by obviating the need for larger more complex tooling.

This is early/mid-stage (TRL 3) — the most realistic path in is NASA SBIR/STTR, which funds small businesses and research institutions to develop technology aligned with NASA's needs (equity-free, phased funding). Check whether a current SBIR/STTR solicitation topic overlaps with this project's technology area, or contact the project directly (above) to ask.

None of these are guaranteed paths for this specific project — TechPort itself doesn't have an "apply" button. Reaching out to the contact(s) above with a specific question is usually the fastest way to find out what's actually open.