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Using EMP To Punch Holes In Steel
angrytuna writes "The Economist is running a story about a group of researchers at the Fraunhofer Institute for Machine Tools and Forming Technology in Chemnitz, Germany, who've found a way to use an EMP device to shape and punch holes through steel. The process enjoys advantages over both lasers, which take more time to bore the hole (0.2 vs. 1.4 seconds), and by metal presses, which can leave burrs that must be removed by hand."
Luckily for us, humans aren't terribly good conductors and thus would be essentially unharmed by an EMP.
Sigs are too short to say anything truly profound so read the above post instead.
The capacitors can probably take several million discharges before there's any "wear" on them however the coils must withstand some degree of stress repeatedly which is a concern over the long term due to metal fatigue.
Sigs are too short to say anything truly profound so read the above post instead.
Hi. I'm a metalworking professional, with a heavy background in tool and die work.
>metal presses, which can leave burrs which must be removed
The burr side, if you've got sharp tooling, doesn't have much of a burr. Also, when you assemble the product, the burr side goes away from the user. Speaker grille material, for example, is always mounted on the finished speaker burr side in. If you've got a large burr punching holes in steel, then you have dull tooling and/or wrong punch-to-die clearance.
>.2 seconds per hole
Too slow. Much, much too slow. Call me when it can equal 600 strokes a minute on a conventional press.
>by hand
Someone's never heard of tumbling, flame deburring, electrochemical mass finishing, etc.
>This article is written as if there's no tooling involved and there's no die or stripper plate to back up the steel as it's distorted by the EMP. It goes on to say that it can do away with molds. LOL QUE?
Total misunderstanding by the journalist.
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BMO
The device works because it induces a current in the conductor (steel in this case) which creates a magnetic field which opposes the field that caused the induction in the first place. This is why you could also punch through non-ferrous metals like Aluminum with the EMP "press." The reason it wouldn't punch a hole through a human is entirely due to the fact that we are poor conductors of electricity which means that it is essentially impossible to induce an electric field strong enough to allow the device to punch a hole.
Sigs are too short to say anything truly profound so read the above post instead.
The magnitude of the induced current depends largely on the inverse of the resistance for which steel is magnitudes lower than human flesh. That means that the field would need to be truly colossal to do the same thing to a human being that this punch is doing to the steel.
ionizing EM radiation certainly. Terahertz can also create bubbles in the DNA helix which can impair proper cell division but there is *zero* evidence that the fields involved in the EMP press do any of this.
The punch works because it induces a current in the metal which creates a magnetic field to oppose the one that induced the current in the first place. It does not depend on the magnetic properties of the metal. This means that roughly anything that is highly conductive like Aluminum, 303 stainless, copper etc. could be punched with the device. Largely non-conductive materials like humans can not be punched with the EMP punch.
Sigs are too short to say anything truly profound so read the above post instead.
I run a water-jet at a university, but I prefer a laser cutter or plasma cutter for CNC work. The water-jet is a pain to keep running. High pressure air and water, tubes, orifices to replace, mixing tubes that wear out, water filters, etc. Maintenance nightmare. I prefer to just have to clean the optics once in a while on a laser cutter and I can tell you that the laser cutter we have cuts much sharper than our water-jet.
The advantage of the water-jet? Will cut 4" of ANYTHING for one thing, and it will cut the brittles like glass and ceramics and stone that the others will not. Also rubber - I cut a lot of rubber with it.
Cheers.