Thursday, March 28, 2013

Gold - How its made

Gold is pricey. I get that, but when all the steps involved in getting the gold out of the ground are lined up - as they are in this video - that priceiness makes a lot more sense.

There's another good tour through the process of extracting gold in the Nova special Hunting the Elements.

How do they do artificial diamonds?

I read an article recently about the possibility of using diamond as a building material. As I watch this video, though and see the massive amount of effort that goes into creating even these relatively tiny diamonds, I'm thinking that we're still a ways off from making any sorts of floors or windows from this carbon allotrope anytime soon.

I love the use of concentrated hydrochloric acid to get rid of the metal slug around the final - and hopeful - diamond.

How It's Made - Plate Glass

The How It's Made series is beautiful, giving us a glimpse into the manufacturing process for so many industrial - and frivolous materials. Here we get to see plate glass being made in the tin float process.


An 180-ton furnace...a production line capable of producing 700 tons of glass everyday for ten years...furnaces heating to 1600 degrees centigrade (funny Europeans)...the scale of this float glass factory is stunning.

There are so many mind-blowing images in this video..

  • the heating at 3:25
  • the giant flames at 3:35
  • the view into the tin bath at 4:30
  • the mass scoring at 6:10
  • the massive warehouse at 7:10
I really want to go to a glass factory. I'm just saying.

Thanks to Pilkington for showing us this glimpse into their factory.

How It's Made: Glass Christmas Ornaments

Much of this video isn't too big on the materials science focus - ooh, glitter being glued on - but the aspect of the glass ornaments not being cooled down too quickly so they don't shatter is a nice application of the thermal expansion of glass and how that can affect its strength.

Plus there's some great chemistry in the inside silvering of the ornaments.

How It's Made: Correlle Dishes

Corelle plates are pretty cool products.

They don't cost much of anything, and they're spectacularly durable, wonderful examples of tempered glass  and the strength that can come from stresses within a product.

In the summer workshops we contrast Corelle plates to other ceramic plates, and the Corelle plates are marvelously strong in comparison. In this video, too, we see that they're even tested for strength before ever leaving the factory.

If you're looking to destroy a few of your own, make sure to double bag them in Ziploc (or an off brand - I like Target's bags) because they shatter into thousands of tiny, razor-sharp shards. And, don't bother with buying them anywhere other than at a Goodwill or a flea market. They're way cheaper there.

Monday, March 25, 2013

How It's Made: the 2 Euro Coin

These two-euro coins are far more interesting than are the coins that we use in the United States. Yes, our coins are partially sandwiched, but we lack the two-part, ringed coins that are used in many countries in Europe. The rings just make the coins way cooler.

They also, of course, make the coins far trickier to manufacture, a process shown in depth in this video.

Mystery of Prince Rupert's Drop at 130,000 fps - Smarter Every Day 86

Prince Rupert's drops (also known as dragon tears) are beautiful explorations of tempering glass - like the Corelle plates that we demonstrate in the first year summer course - using the opposing stresses of the outside and inside glass to create phenomenal strength.

This video does some pretty stunning things with high-speed photography, showing the shockwave travelling down the tail of the drop to the head at over a mile a second.

The video explanation - using red-, white-, and blue-shirted versions of our host - is absolutely brilliant, doing a better job of showing the stresses than any other video that I've seen. Marvelous...stunning...

And, at 4:33, there's a tiny bit of type at the bottom of the screen that tells the actual amount of pressure involved in the Prince Rupert's drops.

Great, great, great video!

Why aren't they wearing gloves, though?

Here's a similar video from Theodore Grey's Popular Science column, Grey Matter.

3D metal printing

This process isn't quite sintering, but it's definitely not forging or stamping or any of the other methods of making metal products with which I'm familiar. It is, however, absolutely brilliant.

Hopefully it's not as wasteful as it looks.

What if: cornstarch

Randall Monroe is the creator of XKCD, a sometimes not-quite-school-appropriate cartoon that involves a mixture of computer-, engineering-, math-, and science-based humor (along with a bit of Randall's personal life mixed in here and there). Randall Munroe comes by his humor honestly as he's a former NASA roboticist and programmer.

One of Munroe's many side projects is What-If in which he answers ridiculous questions using solid science research. Most of the questions are absolutely ridiculous - how would a small plane fly in the atmosphere of Jupiter?, is it possible to create a jetpack by firing machine guns downward? - but every now and again he gives us a wonderful materials science question.

Recently we got "How much cornstarch could I rinse down the drain before unpleasant things start to happen?"

I'm absolutely thrilled that Munroe eventually makes the connection between the conrstarch and the great Boston Molasses Flood of 1919.

PS - personally, my favorite question had nothing to do with materials science.

A better solar-powered water splitter

Metals are just ceramic wanna-be's.

It's something that summarizes so much chemistry, so much material science understanding, and so many problems that we run into with using metals - and apparently with metalloids (semi-metals if you're British).

I'd never thought of the problem of corrosion with metalloids, though it's understandable that even metalloids would 'want' to react with oxygen since all metals do, too.

Cool Stuff Being Made: Cutco Knives

This video seems to have been made by Cutco in-house, so some of the claims might be a little more spectacular than Consumer Reports might just have to say, but this video is a great look at the manufacturing process for a metal material that just about every one of us - and our students - has good experience with.

I can even say that I've owned a few Cutco knives in my time thanks to some former student representatives. I can heartily endorse the fact that they are, indeed, made of materials.

Tuesday, March 12, 2013

Gorgeous photography of the elements

Sure it's possible to take some pretty decent photos with the Kena, and the price isn't too unreasonable. In the long run, though, a great photographer with a really nice camera can just outclass what you and I might be able to manage in the classroom.

( monoclinic sulfur - source)
Yes, there's value in having the students see the crystals grown, in letting them adjust the cooling rate to change the crystal sizes, allowing them to smell the sulfur in the air.

But there's also value in seeing some really gorgeous photos of crystals, like this stunning palladium sample...

(palladium - source)
There are all of these and a whole lot more available over on the Flickr galleries of R Tanaka:

Tip of the hat to Neatorama for posting about these great photos.