Has anybody here ever considered blast welding?

http://en.m.wikipedia.org/wiki/Explosion_welding

Possibly somebody that blows things up for a living?
Using fire to create something is awesome; but doing so with explosions just delights the 10yr. old in me...

Anywho, thought I'd though that nugget out there and see if I get any bites. Lol.

Sincerely,
Crawler.

I saw a segment on Discovery Channel(?) "How Do They Do That?" or something. IIRC they set of a controlled thermite explosion between two very large plates of steel and made them one. Very cool!! (No pun intended) :D

There is a Company in the Seattle/Puget Sound area that has been blowing Steel and Aluminum plate together. It is used in the Boeing/Nasa world. What gets blown up, still can go up!!!

I too saw it on the 'tube. Though, I thought it was Modern Marvels. Could be wrong on that point, cause I watch all them shows (How its Made, How do They Do It?, Modern Marvels, Surviving The Cut, etc.)
Anyway, I thought it was the use of explosions to "sandwich" two dissimilar metals together. Wouldn't thermite do too much melting damage to the lower metal?

Thermite is used to weld railroad rails.

 

 

 

 

 

 

The US Navy used explosion welded steel/alum plate in destroyers. The hull is steel, but the superstructure is alum to keep the center of gravity down and help maintain stability. They use the explosion welded plates where the hull and super structure meet.

I too saw it on the 'tube. Though, I thought it was Modern Marvels. Could be wrong on that point, cause I watch all them shows (How its Made, How do They Do It?, Modern Marvels, Surviving The Cut, etc.)
Anyway, I thought it was the use of explosions to "sandwich" two dissimilar metals together. Wouldn't thermite do too much melting damage to the lower metal?

 

You, and DSW have joggled my memory, Crawler! It was, indeed, The History Channel's Modern Marvels on welding. I love edu tv also :) You're right about the thermite. I thought that it was, but all I could find after googling the episode was "The explosive powder is a proprietary blend of common and unique explosive chemicals. The amount and exact formulation is always matched to the types of metal involved." The thermite I was remembering was on the RR track welding ;)

 

Scott

Isn't thermite also used to cut through rail?

Thermite is awesomeness personified!!!!!
You need iron oxide(anybody here ever seen this stuff?) and powdered aluminum put small quantity in terra cotta flowerpot sitting on two bricks, ignite using magnesium ribbon. Beware this stuff is molten iron on steroids!

One of the few things I remember about Jr high school science class. ( that and how to make dust explosions....)

 

 

I've never seen it used to cut rail, but the military uses it to render equipment unusable among other things.

Coming from an Agricultural background, ( Great Grand-Dad ran a Gristmill ) ... I was well aware of the danger of dust explosions in Grain Bins, ... but had never seen one.

 

 

Until, ..... after replacing a bearing that had been pounded to dust, due to an inaccessable grease zerk, ... I decided that particular machine needed an access port cut into the 5 foot square by 1 foot deep Gearcase cover.

 

I flame cut a 4" square hole in the cover while it was standing on end, ... and then flipped it on it's side to dump out the Grapefruit sized pile of powdered bearing "dust".

 

Obviously, ... when the heavy cover hit the floor, ... with the pile of steel dust trapped under it, ... and sparks from the O/A torch smoldering away, as well .....

 

The resulting dust explosion lifted the #200+ pound cover 3' off the floor.

 

I was standing about an "arms length" away at the time, ... and today ( 40 odd years later ) remember it like it was yesterday.

 

That's the only dust explosion I've ever witnessed / caused :rolleyes: ... but, one was enough to keep me careful, for the rest of my life.

 

 

The explosive power of what was essentially a hand full of DIRT, ... was just unbelieveable.

 

 

 

.

Instructor had a little 1 gallon paint can with a hose going to a small bowl he filled with flour, and a candle. He tamp down the lid, blow in the hose to kick up the dust and when the candle lit it, it would blow the lid off the can. Of course we wanted more and more bang, and he was happy to oblige, at least until the lid blew all the way up to the ceiling and took out the row of 8' fluorescent lights....

 

 

I'd hate to see what they'd do in schools today if he tried to do that. Probably have half the local swat teams from 3 counties converging on the school...

If I remember correctly the metal used to make US coins is blast welded.

If I remember correctly the metal used to make US coins is blast welded.

 

No ! most US Coins are Stamped into "Slots" (the round form), then the edges are formed , and finally the face and back are pressed by a Hyd. ton Press to form the face and back at one time .

 

R&R track is cut by a Hyd. Controlled Power Saw with a carbide blade and the unit is fitted to the track so X & Y Cuts are Square and Straight . so the track can be removed and put back together in a seamlessly manner.

 

Ret,Sgt. Yates

Blast welding would be far too cost prohibitive for coins. Though, I can see how one would come to that conclusion. When you look at the the edge of a quarter, you can often see a distinct line of (silver colored metal substance) and (brown colored metal substance). I'm rusty on my numismatism (spelling?), so I can't swear that its how they do it, but this is normally easily achieved through plating.

Sincerely,
Crawler.

It appears that the strips of metal used for coin blanking are cold formed by roll cladding: forcing two layers of cupronickel over a core of copper in a high pressure roller die. The result is long coils of metal easily fed into blanking machines, not the square sheets that you would get from explosion welding.

I second the cladding vote. (Saw it on History Channel....I think ^_^ )

That would explain why you can see the different metals on the side. If they were plated, the coating would likely wear much faster on the two faces.

But still, blast welding is neat!