# Welding without heat...

Discussion in 'General Science & Technology' started by cosmictraveler, Jan 19, 2008.

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1. ### cosmictravelerBe kind to yourself always.Valued Senior Member

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I was giving some thought of how to bind two metals together without using any heat or welding wires/rods and an idea struck me. Seeing that the atoms are similar to each other why not excite them using a frequency that would be applied to make them energetic enough to just bond together? If a sound frequency could be found that could make the atoms so energetic couldn't this actually be done? Just a thought, what's your thinking along this line?

3. ### spidergoatum... what?Valued Senior Member

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Sonic fusing is a common way to join plastics. They probably do it for metals too, but metals do this naturally. Perfectly clean metals will fuse to each other instantly.

5. ### cosmictravelerBe kind to yourself always.Valued Senior Member

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What about steel? Have you ever heard of steel being "fused" this way as well?

7. ### spidergoatum... what?Valued Senior Member

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Any kind of energy that will heat the metal up will work. Sound energy is as good as anything. "energetic" is the same as heat.

8. ### cosmictravelerBe kind to yourself always.Valued Senior Member

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So why hasn't anyone come along and made a sound wave welder? It would be cheaper and easier plus better for the metals to combine with.

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Easy - because it's SUPER dangerous under any conditions other than factory applications (which is where it's also applied to plastics - as was mentioned).

The transducer is impossible to control by hand and the welder (person) would be injured immediately by the stray (powerful!) sound waves. It's also conducted by the metal even better than through air so there is no safe place anywhere near the operation.

Edit: and forget about ear protection - we're talking about BONE conduction.

10. ### cosmictravelerBe kind to yourself always.Valued Senior Member

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So why not use electromagnets to attach the device onto the pieces that need to be fused together and leave it without anyone around it until its done with its job?

11. ### Echo3RomeoOne man wolfpackRegistered Senior Member

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"Making the atoms energetic" means heating them up.

Plastics can be bonded chemically with certain saturated solvents absent heat, but not metals.

...beaten by spidergoat

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wow

13. ### FacialValued Senior Member

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Sonic welding has been done on aluminum since the 1960's. They have also tried it for steel, although you need to heat it up a certain degree.

It shows much promise. You might be able to clear a free surface by abrading in oil or a nonreactive liquid, then applying ultrasound to assist the free energy spontaneous bonding in metals.

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That sounds like a far too complicated process if you're doing more than just a quick and fairly simple job. And for something of THAT nature (quick and simple) it would still be pretty complicated and expensive. Just grab the old arc welder or MIG/TIG and be done in a few minutes. :shrug:

15. ### cosmictravelerBe kind to yourself always.Valued Senior Member

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I was only considering a device that large for BIG pieces of steel to be welded not smaller ones. I don't think smaller ones would be as hard to use the device with because a small job would only need a small machine to weld it with, not a large machine.

16. ### cosmictravelerBe kind to yourself always.Valued Senior Member

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To weld witout heat with LARGE pieces of steel is something I've come up with. No one seems to understand how to do this but myself, to bad.

17. ### FacialValued Senior Member

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I'd like to hear what you've come up with, cosmic. Because it can overthrow just about everything in the welding and construction industries.

18. ### OrleanderOH JOY!!!!Valued Senior Member

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I hate sonic welding. Eventually you get used to the high pitched squeal, but...eeeeeeeeee for hrs, is spine tingling.
Lots of parts in your car are sonic welded.

19. ### spidergoatum... what?Valued Senior Member

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They have.
http://en.wikipedia.org/wiki/Ultrasonic_welding

I maintain that metal will weld with each other with no added heat if the mating surfaces are perfect, and there is no oxidation. I used to work at a company that produced a cold-welded material for dental fillings. The material was just a kind of metal with a coating of copper. It's easy to remove the oxidation from the copper with an activating solution, after which the metal particles naturally weld to each other.

A film of oxidation or foreign material is the only reason metals don't weld to each other when touching.

20. ### FacialValued Senior Member

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It's easier to do for low-$T_m$ metals like dental amalgams, solder, tin, aluminum, and even brass, but much harder to do for other metals such as iron and titanium.

You have to heat close to the creep temperature (roughly $0.4T_m$) to successfully use ultrasound welding on them. Solder creeps at room temperature, and aluminum can creep at around the boiling point of water.

21. ### Dr_ZinjRegistered Senior Member

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I think cosmictraveller is referring to a process of chemically welding two peices of metal together. It's a fictional device used in the Honor Harrington novels by David Weber for spaceship construction and repair. Whether there is a real world capability of doing this I just don't know.

22. ### Walter L. WagnerCosmic Truth SeekerValued Senior Member

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Gold will naturally cold-weld to form alluvial gold nuggests. Flakes of gold wash down, settle into cracks in a stream-bed, and form alluvial nuggets over long periods of time. This gold is much more valuable than ordinary gold, as it is prized by collectors.