The Creation of Metal Bubble Wrap

Bubble Wrap may be getting a much needed upgrade. A new design of Bubble Wrap created with a composite metal foam is being created to better absorb impact.


[ Bubble Wrap popping ]

It's the same concept, again, coming back to Bubble Wrap.

When you wrap your vase, glass, a jar around, that cushion ability come from those bubbles is what protect your material and the same concept here, the cushion ability of these hollow spheres but in a higher stress level.

So think again about Bubble Wrap.

The packing material works because the air pockets in the wrap absorb the energy of an impact by changing the shape of the bubble.

The same is true for cardboard and Styrofoam and packing foam.

The packing material may be crushed, but the cushions of air, the spaces between the material, absorbs the energy of an impact.

It's that concept that inspired the creation of composite metal foam.

What we did was to introduce the same concept to metals, and now we have the impact protection because of the porosities inside, exact same concept as Bubble Wrap or Styrofoam box for egg carrying, but this time, you have it against much heavier impacts, and the same concept with heat.

We put our material against fire.

Just watch.

The metal foam is on the left.

The blast is from a high-explosive incendiary round.

It's hitting the metal foam at 5,000 feet per second.

The shells were shattered.

The foam was hardly damaged.

So this is the armor-piercing.


That's what they fired, and that's what was left of it?


After it hit your foam?

Yeah, we actually collected this from the sample.

I was eager to see how it works, so I was so tense, and then once I heard that it didn't hit, so I kind of relaxed, but, you know, my last test was against very, very large bullets, something, you know, in these kind of size.



And these are really large, and when it actually stopped a bullet this size with 10 layer of the material we had, I just ran, and I hugged the guy who shot my sample.

He shot your foam.

And he's such a nice guy.

He's like, everybody congratulating.

Again, just like in Bubble Wrap, the strength in metal foam lies within those spaces.

This is the first time I could show that composite metal foam can go through 80% compression without damaging, so you can see that all the spheres here are squeezed down and absorbed the impact or compressive energy.

Going from this size to that size was kind of...

That size to that size?

To that size, yes.

Everything was compressed, but that's because it absorbed the energy?


It absorbed the energy.

It's exactly what I told you earlier about the Bubble Wrap, squeezing down, press the bubble or something like... This one, all the spheres are squeezed down and absorb the energy.

So this was the beginning of my story, when I could do this without this falling apart or bulging or cracking.

You knew you had something.

I knew I had something.

I called my family.

I said, 'Oh, it squeezed down to 80%,' and there were like, 'Uh-huh.'

[ Both laugh ]

'Okay. Who cares?'

No, they care, but they didn't really know, what does that mean, but it's a, 'Okay, congratulations.'

[ Both laugh ]

But it turns out those spaces not only make the foam strong, the spaces also reduce the weight.

This is made of stainless steel.

Here is almost 1,200 gram, and this one is almost 400, so it's almost a third.

Right, a third the weight but stronger.


It's much more energy absorption.

It's almost two order of magnitude energy absorption, higher energy absorption in compression, mostly in compression because those spheres are giving the cushion ability.

That's what makes my material unique.

The spheres are distributed uniformly, and they are the same size, and there is a matrix in between the spheres that strengthen the spheres.

Strong and lightweight is a good combination.

The metal foam can also be customized to fit the application, adjusting weight, thickness and shape.


So this time, I'm showing you aluminum with aluminum-steel composite foam, meaning that the matrix in between the spheres is made of aluminum, and then the spheres inside it is made of a steel.

So this is an aluminum-steel composite foam.

This one, the aluminum block, is 300 gram, and the other one, the composite foam, is almost half.

More tests with the military are planned.

Metal foam could also be used by law enforcement, emergency personnel, hazardous materials operations.

In fact, the list of possible applications is almost endless.

I am super excited.

I cannot sleep at night because I keep thinking, 'How am I going to take it to the market?

How am I going to help this technology to reach where it, you know, where it should be?'

And that wraps it up for this time.

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Until next time, I'm Hari Sreenivasan.

Thanks for watching.

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