If vibration damping is your main concern, TPU might seem like the obvious choice, but it can be too flexible, which might cause the fan to shift or vibrate excessively. A rigid material with some damping properties is often a better balance between stability and vibration reduction. Alternatively, a TPU part with a rigid part inserted into it can give you control over the final stiffness.

For this kind of application, PA12 (Nylon 12) is usually the best option. It has excellent impact resistance and some natural vibration absorption while maintaining structural integrity. If you get it printed using MJF or SLS, you won’t have to worry about infill settings or layer thickness, as these processes produce solid, high-quality parts with uniform properties. The beauty of MJF is you can select the material stiffness as it co-prints which allows rigid/flexible revisions by mixing on the fly.