Partnership with NCSU on Project CRUCIBLE

Partnership letter with NCSU for Project CRUCIBLE (Conductive Refractory Ultra-temperature Components for Integrated Broadband Low-loss Environments).

Radio energy travels down the inside of waveguides, and for the antenna to work, the pipe has to hold its shape at temperature and carry the signal without losing much of it along the way. Those two requirements pull in opposite directions in extreme environments. The metals that hold their shape when things get hot, including niobium, tantalum, molybdenum, and tungsten, conduct electricity less well than copper. Swap in the heat-tolerant metal and you keep the geometry but give up signal.

Project CRUCIBLE starts from a less obvious observation about where the loss actually comes from. At the frequencies involved, the electrical current does not flow through the bulk of the metal. It flows in a skin near the surface roughly a micron deep, which is about a fiftieth the width of a human hair. Parts made by 3D printing come out of the machine with surface texture on that same scale or larger. The current has to travel over that texture, and the extra distance costs signal.

Once you frame it that way, the important question changes. It stops being which metal to choose and becomes how smooth the inside of the channel can be made. That matters because these are closed internal passages, so ordinary polishing tools cannot reach them. The work for Project CRUCIBLE covers finishing methods that flow abrasive or chemistry through the part, thin conductive liners that survive the operating temperature, and oxidation protection, since some of these metals burn readily in air well below the temperature at which they lose strength.