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tlfamm
10-09-2015, 10:51 AM
From the Modern Marvels cable TV series:

https://www.youtube.com/watch?v=2u51tJdRDK0

No great technical depth, but interesting nonetheless.

boslab
10-09-2015, 05:22 PM
Not something I'm going to try!, a lot of plates get rolled after to coils of steel, or whatever the case, nickel clad is common for tanks I'm told
Mark

kf2qd
10-09-2015, 08:45 PM
Used to have an interesting slug of explosion welded material. Scrap from a submarine piece that was waterjet cut. 1/4" titanium explosion welded to 5/8" stainless. Done in 4x8 sheets. Occasionally they would find a bad spot where the 2 pieces did not bond.

Mike Burch
10-10-2015, 04:39 AM
An interesting video. But no explanation of what happens to the spacers. Presumably they get squashed flat, but surely they must introduce some local anomalies?
Attaching an aluminium superstructure to a steel hull and deck is sometimes done by welding each part to the appropriate half of a bi-metallic strip that has been explosively welded together.
This is stronger, less likely to develop leaks and less prone to corrosion than simply bolting them.

A.K. Boomer
10-10-2015, 10:38 AM
Someone else brought this up about a half year or so ago - really is incredible and sounds expensive as all hell but just amazed that it works so well and they actually have it down to a science...

tlfamm
10-10-2015, 02:17 PM
Used to have an interesting slug of explosion welded material. Scrap from a submarine piece that was waterjet cut. 1/4" titanium explosion welded to 5/8" stainless. Done in 4x8 sheets. Occasionally they would find a bad spot where the 2 pieces did not bond.

What technology was used to find the bad spots - xrays, ultrasound, etc?

kf2qd
10-10-2015, 10:58 PM
What technology was used to find the bad spots - xrays, ultrasound, etc?

Would not cut through the second layer and water would spray everywhere.

Duffy
10-10-2015, 11:27 PM
This process has been around since just after WW2, but it got a boost with the development of rubberized sheet explosive. There was a whole series of metal combinations under the trade name of Detaclad. Where it really shone was in applications such as high temperature/pressure heat exchangers, since the liner could be expensive, thin and unreactive to the chemicals, while plain steel withstood the heat/pressure.

boslab
10-11-2015, 12:56 AM
Apparently hilti nails in steel weld at the surface layer, I wouldn't be surprised if they did, we used to tag slabs with a cast number by nailing the tag onto the end of the steel slab, there would be no problem firing a 20mm nail into a solid steel slab, you wouldn't be able to pull one out, the guy from hilti reckoned there was a weld between the nail and substrate similar to explosive welding, the longest nail they were able to fire into steel was 80mm, the nail was gold plated for the test, we sectioned that one and polished it, there were patches of fusion but I don't think that size would qualify for "welded", I would think explosive "fusion" would be more appropriate, there wasn't an explosive version of a HAZ, one metal ended, the other started, I couldent find any kind of alloying between the 2, they were just well stuck!
Tagging slabs was a sucky job, the hot slab tagging being special torture, a stack of steel 10 " thick plates glowing, and you get to walk up to them with a hilti DX450 gun and nail a tag on each one, you could smell your visor melting, smoke coming off your jacket, you didn't hang about.
What I'm wondering is if the plate was put onto a formed shape could the explosive process form 2 plane curves easier than torch and water, like steel spheres, ships bows etc, something to think about
Mark

Duffy
10-11-2015, 10:13 AM
Regarding explosive forming; back about 1973, there was a company forming bell housings for high performance engines. They claimed that their product could contain the fragments from a disintegrating clutch, whereas a conventional diecast unit would not. I THINK that the company was called Lakeland and their market was stock car racers.