No stupid music, no fancy presentation, no pointless bla bla. Just 100% science. Pure gold !!

That was extremely well done. At one time I was the supervisor of the chemical strengthening process in a glass plant, but our liquid potassium vat was large enough that we could strengthen glass up to 36x48 inches. A few differences were that we kept the liquid potassium at 650C and we soaked the glass for about 8 hours in a batch process. We also let it cool slowly once it finished the soak. Unlike thermally tempered glass, chemical tempered glass can be cut like ordinary glass, however cutting the glass removed the temper along the length of the cut about an inch or so to each side of the score line. Also a deep scratch in the surface would also remove the temper along the scratch line as well. We would test the process by weighing 1"x1" samples, soaking them in the bath, and then weighing them again after they cooled. We could compute the compression level by using the difference in weight between the samples before the bath (sodium) and after (potassium). The balance that we used to weigh the samples was so sensitive that we could weigh a mosquito. We even weighed a mosquito wing one time.

If we ever need to rebuild civilization, I know I will swing by Ben's house and he'll just do it in a week or so.

What's that sound...? That's the sound of Corning's corporate assassin helicopter.

Nice use of props for the explanation. Very effective.

This channel is pretty much Mythbusters without the unnecessary tv BS. I love it. Great job.

Just discovered your channel. I'm a mechanic by trade (but by no means an engineer), so i really appreciate this content. No fussing about, just top notch craftsmanship and science. I tip my hat to you, you are exactly what a true engineer should be like.

Superb demonstration and explanation! FAR better (more concise and clearer) than my engineering and material science classes!

The treated glass will resonate with a higher frequency when struck, so this could be used to measure how much substitution has taken place. Perhaps substitution with caesium might enhance the effect, being a larger atom than potassium.

I really dig your video production style. Simple, elegant and to the point of the subject. You truly involve the viewer and that is how the best kind of learning takes place. Thank you for doing this.

"Preloading it in compression" - soo, kinda like Prince Rupert's Drops? That's awesome.

Its fantastic being able to hop on here and learn from experts like this! Cheers for uploading Ben

Similar effect as in prestressed reinforced concrete. I never saw this coming. Love your channel man!

So complete and clear explaining! I enjoy and learn from every video he made. Much thanx again to Ben the man!

Interesting Ben - Like carbon entering into an iron lattice and creating steel. This silica glass you treated could be considered a metalloid alloy!

Greatly informative video! You always have the best projects, not in just the applications but also the explanations.

Great video! I've recently started a post doc on an alternate way of strengthening glass, this was really helpful! Thanks! Keep up the amazing videos

You have great videos. I appreciate the depth to which you explain things. Thank you!

These are EXCELLENT explanations. Nice work!

I think this is one of the most interesting videos you made. (Maybe the most for me) Probably I'm gonna use this method for my work. Great job! Keep it up!

This video made me break out my old material science book from school and scan through a few topics. There is actually this exact 3 point loading system described in detail; to test the flexural strength of brittle ceramics. Interesting stuff. Had me reviewing defects, slip planes, fracture mechanics for the last hour or two. lol .. cool video.

Your channel is amazing, thanks for sharing your knowledge.

It's a great explanation how they produce toughened glass. Thanks for sharing.

Excellent video! Very interesting bit of chemistry. Keep em coming!

I wish this was used as an example in my mass transfer class. Would have made things very interesting! Thanks for the amazing work.

I love watching your videos. I learn so much.

Very interesting your exposition thank you so much for shering that knowledge with us .

Amazingly clear explanation. Thank you.

Excellent Explanatory video ! Great Job !

Excellent explanation and demonstration as always!

I love your logo it fits the channel perfectly 💯

I saw you flinch! :) I am envious of your playground, and of your creativity and the things you build and test. Really good stuff sir. Bravo!

Always when I watch videos of this channel I feel like there should be way more like buttons on youtube...

Excellent job as usual!

I was listening to the glass lecture.... until I saw 70+ farads worth of capacitance in the background....

The key ingredient for toothpaste used for sensitive teeth is KNO3 too. It is used for filling up the very small tubules in the calcium material (dentine) that lead to the dental nerves. Obviously, it is used at room temperature, but I guess that it is just that KNO3 is especially good for filling up defects in hard materials like silicon and calcium compounds. Great video. Thank you.

Your are surely The Man of Multiple Talents.

Great video and very well explained. Thanks a lot

Very good demonstration. Since the edges are the weakest point, it is important to start with glass that has a clean cut (no chips) or a machine finished edge to make the glass stronger.

Very useful. I have a prototype project at work where making toughened glass is useful to me.

Wow man, awesome information. Cheers from New Zealand.

Awesome video. Nice to finally know how these stronger glasses actually work.

You are an amazing teacher, my profs wave their hands wildly instead of cool examples like these

Great! Just noticed, that I like 2 more of his videos, and HAVE to watch them now...Despite of not having time at all anyway!!!

I saw a great demo on TV of the effect of defects in glass decades ago. Take about 4 inches of 1/4 inch (say) glass tube and heat it in the center and draw it until very fine. Then mount it in a couple of holes in a piece of wood such that the drawn section is bent 180 degrees. Such a thin piece of glass is very flexible and all is good. However on touching the outside of the bend in the glass with the edge of a feather it immediately shatters. The nascent drawn glass has few defects and the feather introduces some.

easy listening. great voice, well presented. bulk information. nothing to trim. cleanest channel on youtube :)

That was fascinating! As a retired glazier, I am impressed. I thought only heat could strengthen glass. I am old. ;-)

This guy is amazing. Looks like ha makes all kind of test fixtures. It looks like the cart in the background was homemade.

great explanation as always!

another excellent video. Thanks!

Great video. The process is so simple thanks for showing this. Question how much bigger could this be ramped up. And does the glass's shattering characteristics change.

thats really cool- reminds me of the process that happens to clay sheets with atomically large ionic salts.

Wish I could run my Coleman stove for 3 hours to try this.... As always a cool project, keep them coming!

All I can see to improve upon would be to somehow reduce the inherent defects of the glass surface, the cracks, somehow. Perhaps another chemical or other solution could be added to this process post potassium saturation to further smooth out or full in those microscopic defects. Not being of a chemistry background or such I don't have any idea there. It might not be possible or even necessary to do my suggestion. If chemically unfeasible then there might be some "mechanical" means to further reduce the small surface cracking via heating, polishing, etc. though the simplest idea I just had was some sort of lamination. A film or another glass layer or such ... but your explanations here and demonstrations too were very well presented, easy to follow, and got my mind thinking about solutions to a problem I haven't ever considered to be a problem to tackle in my lifetime. Thank you so much for the brain workout and your efforts to make an informative well presented video.

Great way of seeing the concepts I learn in class actually play out

Great video, your experiments are truly the best. Any thoughts as to further strengthening of glass utilizing atomically larger group 1 elements? Such as Rubidium or Cesium salts.

That's... honestly fascinating. I know most types of glass put in public places are (heat?) treated so that when they break, they do so into little cubes as to avoid sharp pieces that could potentially injure someone, but I never knew something like this was possible.

love your work

0:47-0:48 I still think that is the best part. Just the concern that is shown for safety. Like, it is only a glimpse and not forced into my face and demanded, but it just shows what you do and your precautions that you take. It is a good way to talk kids into being more safer being that most kids rebel when it is insisted upon. Intentional or not, many pros for that bit.

Very educational, thanks !

Your videos make me smile :)

Very cool. Almost like "case hardening" for glass.

Thanks! Learned something new.

Very interesting! Does this mean that if you treated only one side of the slide, it would bend?

Awesome! I was hoping you would work on this one. I may have to use it for some of my own projects (the un-breakable beer bottle).

Great video. Thanks.

I would view this demonstration as pure Magic if it were not for Physics & Chemistry, still beyond all other considerations itz splendidly Magical! ;-)

Once again a brillant video. keep up the great work. Its almost scary to think what you could get up to if you retired and did they stuff full time. LOL.

hi ben, if the strengthened glass is heated and formed to some random shape and back again to a slide then will it still retain the strength or defects will be induced again during the heating and forming process.

I really appreciate all the pains you take to thoroughly explain the science behind all your projects, also, does this treatment protect against chips in the corner for example? i'm thinking of attempting this because it reminded me of the container of broken microscope slides i have sitting on my shelf :) thanks for the vid!

very... good video

Great video!

I don't have time to watch your videos, Ben. Oh look, a squirrel! :-) Awesome as usual.

Great video

That was interesting, thanks!

Finally, pictures!! Now I understand!! :)

Very cool, thanks

Man who are you? your videos are freaking awesome. How did you learn to do all this stuff.

Very neat! Prince Rupert drops via chemistry. Thank you!

Kind of like post tensioning a concrete house slab. I had one of these when I lived in Louisiana and the soil was very soft. The concrete slab was in compression and did not crack.

It's cool to see you working with glass It would be interesting to see if you could figure out a diy coating system To help with flare and chromatic aberration on old camera lenses that didn't originally have coatings.

Just like pre tensioning concrete. Very interesting.

You are living the dream man... Taking physics and chemistry I always had ideas of how to apply the stuff I was learning but never had the chance. One day.. I wanna be just like you. Also, I just read a paper on piezoelectric nano technology that applies something similar here. They took a thin layer of Mos2 and bent it like you described to create a current at the nano level. Super cool stuff. Im starting to think I am an engineer rather than a biologist.

Nice work and presentation. I like it. How this process differ / same than the another one known as glass tempering ?

This process reminds me of the relationship between concrete and high tension cable in (post tensioning).

SOLID VIDEO!

great vid, thanks

Interesting as always thank you, i wish you would have gotten more in detail about the nature of glass, what it is and why can't the defects be removed from the "structure", how glass is more or less by opposition to crystal and how glass is produced, not necessarily in detail but an overview on what glass is, what are the characteristics and how it is produced through applied science :)

This is very cool. The diffusion process seems to only be possible at high temperature though. Since Na ions are smaller than K ions, the glass would need to thermally expand if no pressure is used to cram in the new ions. My bet is that borosilicate glass wouldn't respond as well to this treatment because of its low expansion coefficient. Additionally, you should try this same process under pressure!

thank you, very informative. :)

very informative thank you sir ,

Great content

Great video. If you did this with prescription lens glasses do you think would it change or effect the magnifying level optics?

I need to try this with some old used fluorescent light tubes I have and see if they will become tough enough to use for solar collectors.

Great demonstration. That's fine for constant pressure loads, but what about sudden impact like a drop from height. Or something falling onto the glass. Most phones are broken by falls and the such. Just something for you to think about and experiment with.

Nice! Very educational & trivial. Thanks. :) (y)

hi, thanks for this interesting video. However I have a safety question regarding postassium nitrate: do some small explosions happens while heated up? also are there any fumes that are delivered while heating up? Would it also be possible to put together the powder and the glass without having to open the klin to put the glass in? Thanks

Hi, interesting video. How did you build the kiln used in the video? In particular, which is its temperature range and what kind of heating elements did you use? What material is it made of? Thanks!

Hi very nice channel and video. Given that glass is a super cooled liquid, how long will this effect last, since it will slowly and eventually relieve itself of the internal stresses?

Any learned Glass Blower knows that by increasing the wall thickness and tempering process also increases the compression strength there by interleaving the tension stress to the opposite wall of a given cylindrical glass pieces.