Dampening material

[aldumoul]

We typically use Ductile Iron 65-45-12 for spindle housings. This is a great material as it does not seem to get excited at a wide range of speeds (natural frequency). However, we have had a lot of requests for a much lighter solution for applications in robotics. There are other factors to consider such as hardness and thermal expansion. But to start with, I am wondering if anyone has any materials in mind that are worth looking into? Max speed is 7,000 RPM.

 

[btrueblood]

Magnesium has some good damping as well. Realize that moving to a non-ferrous alloy will significantly impact the stiffness of the housing.

 

[EdStainless]

Many lightweight alloys have a higher specific stiffness (modulus/density) than cast iron, but in order to get a structure that was as stiff you would need a radially different design.
Honestly you might be better off consulting with someone experienced in composite design.
That might be the only way to get lighter weight and keep the stiffness and damping high enough.

 

[dik]

I would think any material with the largest hysteresis curve for loading and unloading.