Small cylindrical parts are often formed through deep drawing — a process by which a punch forms the finished piece from a flat sheet of metal using a forming die. If it sounds like that stresses the metal, it does. But researchers at Fraunhofer have found a way to reduce friction protecting both the material and the tools that do the forming. The process — known as VibroDraw — uses ultrasonic vibrations at around 500 Hz.
Researchers claim a 20% reduction in friction now, and it may be possible to go even further. With less friction, it is possible to do a deeper draw in a single stage. It also creates less heat which is good for tool life and prevents overheating lubricant. The process has a patent if you want more details. You might need to brush up on your German, though. Unsurprisingly, the vibrations are from a piezoelectric transducer.
Copper is soft enough to use 3D printed dies. We don’t know if this technique would help with that or not. Then there’s hydroforming. If you have any results using ultrasonics with these or any other techniques, be sure to let us know.
Looking forward to a Hackaday article on explosive forming…
Probably as close as you’ll get for now (world’s least comfortable throw pillow):
https://hackaday.com/2014/08/13/hydroforming-in-the-garage-with-a-pressure-washer/
Double plus good!
Anything to lower the cost of ammo.
500 Hz isn’t ultrasonic as far as I’m aware, but it is still the same general idea. You could actually hear this, for example. I wonder what it sounds like. I know what a 500hz sine wave sounds like but I doubt this makes a perfect sine wave.
Since when is 500 Hz “ultrasonic”? May I suggest that someone proofread posts before posting.
…Also you can use 3d printed dies for all kinds of metal, as long as you don’t mind it wearing out very quickly:
https://www.youtube.com/watch?v=KTnaALsKpH4
The VibroDraw link links to a Hackaday admin page.
Well, this is an odd link to “the source” https://hackaday.com/wp-admin/post.php?post=766967&action=edit
….
Managed to snag an ultrasonic processor for $30 on eBay 4 weeks ago, and just last week figured out how to use it to drill a hole in rock pretty reliably.
Haven’t figured out how to do glass or metal (maybe that’s not possible with ultrasonics), but when I’m satisfied I’ll write it up and submit it.
Maybe I’ll try this process as well.
Lots of ultrasonic processors and things available on eBay, but they’re usually 10x as expensive.
The patent mentions 15 kHz and 20 kHz generated by piezoelectric transducers, which is where the confusion arrises for a patent called “Deep-drawing or wall-ironing device and deep-drawing or wall-ironing method with ultrasonic superimposition”. The vibrations used are not always in the ultrasonic range.
500hz is about 26 hz shy of Middle C
Maybe 500Hz is the modulation freq?