How to chemically strengthen glass (eg Gorilla Glass)

[@francoisdastardly4405]

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

[@breilly2750]

@spim randsley well...you're here, aren't you?

[@breilly2750]

@spim randsley okay, then. You can go back your cartoons now and not learn anything. I find these videos fascinating since I'm a professional in a completely different field and never had the chance to learn some of the science this channel explains. I'm sure you can find a video on KZbin about how to wipe your own ass. Go find it.

[@breilly2750]

@spim randsley yes, I'm pretending to dig a hole....but you're the one actually digging a hole. Don't go there. You're comment was imbecile and that's all I needed.

[@breilly2750]

@spim randsley You know, I was going to ask you the same thing. I seriously would have loved to have been there when you realized that you needed to Google the word "imbecile". Stop being an asshole.

[@TheDanielConsole]

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

[@cassiwithoutane]

i know this comment is old but i'm hoping you've seen adam & jamie's videos on "the glass age"!

[@RimstarOrg]

Nice use of props for the explanation. Very effective.

[@taboosaboo]

Agreed. & Making Viable Claim to Tension Defect,. But torsion was observed. There was no determinate distinguishing otherwise. ...what of fiber glass? Hammers fare well?

[@lancelotxavier9084]

That was a prop?

[@anatexis_the_first]

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.

[@gregcorwin8316]

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.

[@unvergebeneid]

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.

[@seigeengine]

Why are you up in all my smart things? D:

[@skson5838]

... but only if he is not the one who destroyed it :)

[@unvergebeneid]

seigeengine Sorry ;) I guess "smart things KZbin" is still too small a place.

[@AtlasReburdened]

Your nuts. That type of man knows he's too valuable to risk on strangers. You'll get within proximity and a 400W CO2 laser will grid pattern you to death, or he'll just shoot you in the chest or something less dramatic like that.

[@James-fe7wd]

What's all that got to do with his nuts?

[@learnerlearns]

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

[@ronaldschild157]

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.

[@grey7603]

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

[@donaldklopper]

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

[@robson6285]

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

[@DavidKirwanirl]

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

[@ahaveland]

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.

[@toolhog10]

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.

[@JohnAudioTech]

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.

[@toddburgess6792]

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

[@sasjadevries]

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

[@nikolaijelinek3869]

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

[@FranLab]

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

[@Falcrist]

I absolutely love that the KZbin science channels are a community, and you occasionally comment on each other's videos.

[@sarowie]

Except that when making steel, it usually starts with "iron" with a high (>2%) carbon content. Carbon and other impurities get removed in the process of making steel. And other metals and maybe carbon get added, creating an alloy. But all of this gets done with liquid metal, not with a solid piece. If you would like to compare that to steel, then look up Carbonitriding.

[@melody3741]

OMG ITS FRAN

[@zilog357]

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.

[@ElectronFunCom]

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

[@murraynano]

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

[@armonnaddaf5326]

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

[@GothicPotato2]

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

[@springford9511]

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.

[@Gianma89]

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!

[@TheRogerx3]

Your are surely The Man of Multiple Talents.

[@highwaltage]

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

[@PunchDrummer]

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!

[@spinafire]

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

[@wtechboy18]

It's basically exactly how tempered glass works. Cooling the outside rapidly shrinks it relative to the core. Then when the core cools, it tries to "suck in" the harder outer shell of glass and puts the core under tension and the outer shell under quite a bit of compression. I'd be interested to see how this process worked on tempered glass, come to think of it.

[@SlowerIsFaster139]

in curious as to how sapphire behaves. it might be completely irrelevant but, maybe they share some properties? idk lol

[@NathanMichalik]

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

[@zetag055]

These are EXCELLENT explanations. Nice work!

[@NinjaOnANinja]

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.

[@orbmanelson]

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

[@RasmusSE]

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

[@markbell9742]

Hi Rasmus SE, I had the same thought. Ben could you make a run trying to only treat one side of the glass. Cheers, Mark

[@lukedowneslukedownes5900]

Who else randomly got this in their recommended😂 I’m not complaining tho, this guy’s an OG

[@Mrcometo]

Great video but there is an error in 5:57 : precompressed members will be not in higher compression in the compressed fiber. The compresion stress will be be the same as precompressed till the external forces increases to a point in which it led the material to a higer compression stress, but till this moment, compression stress will be constant. It is the same for pre tensioned bolts in bolted flanges.

[@beatrizremigio9192]

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

[@TheMattiePoo]

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

[@t-rodshader9593]

Lol. First table second shelf

[@smellycat249]

I love watching your videos. I learn so much.

[@hirmaguma3367]

Excellent Explanatory video ! Great Job !

[@tysondeal4369]

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

[@scotttaylor215]

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

[@justinhamill954]

I love your logo it fits the channel perfectly 💯

[@MrClaudiodonate]

Just like pre tensioning concrete. Very interesting.

[@mikeissweet]

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

[@steveastrouk]

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

[@old_guard2431]

Two points (which may or may wnot be pointless): First: There is a superficial similarity between this process and case-hardening steel. In case hardening steel is packed with a carbon source (typically charcoal) and heated in an air-tight container to a temperature well below the steel’s melting point, infusing the surface with carbon to harden it. Making it stronger but more brittle. Second: Whoever first discovered this technique was doing some seriously creative chemistry.

[@PackthatcameBack]

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.

[@krausrepair1171]

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

[@NickMoore]

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).

[@aleksanderbl9381]

would like to see that!

[@BlackPhanth0ms]

Tiddly Penguin Cans can't really be reused easily.

[@vsiegel]

Nick Moore - Beware, the "un-breakable beer bottle" will kill people! Beer bottles have a common use in bar fights - and a breaking bottle may prevent a skull injury. Also, it will soon be used as artillery projectile. Fill it with something cheap or heavy, like molten steel or uranium. The only reason not to use tungsten is that is so hard to melt it! And nuke tests will be done again soon! But physicists will be really happy!

[@dantennison1153]

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.

[@arcadeuk]

Excellent explanation and demonstration as always!

[@JRo250]

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

[@lmeza1983]

Your channel is amazing, thanks for sharing your knowledge.

[@jakenbaked87]

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!

[@glenbartholomew1058]

Good job, nice demonstration. But I was hoping you would test for the strength of the glass you made also. Adding that would make for a more complete demo experiment.

[@qOvob]

Glen Bartholomew he did, watch again.

[@ernestoterrazas3480]

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

[@thingsofsuch]

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.

[@brandtAU]

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.

[@Gooch_cruiser]

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.

[@troywhite6039]

Bioengineering, the next big thing.

[@metrologic5000]

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.

[@Pilot_engineer_19]

Excellent job as usual!

[@akshaykumarvyas]

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.

[@honawikeepa5813]

Wow man, awesome information. Cheers from New Zealand.

[@piranha031091]

Is that a huge capacitor bench I see on the left of the image? Is it for your YAG laser project? Aside from that, it would be nice if, just for the sake of comparison, you weakened glass by ion exchange with a lithium salt! Thanks for making those videos from you home laboratory (which I'm quite admirative of by the way!), you're one of the few youtube channels which provides actual scientific content that has not been completely dumbed down!

[@BluntForceTrauma666]

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

[@klausbrinck2137]

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!!!

[@ZakarooNetwork]

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.

[@keeganmaloney3440]

It seems like we would have a better way of solving this problem by now. I am curious about why it is so hard to remove or prevent imperfections in glass. Is it just impurities?

[@DeliciousDeBlair]

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.

[@questorhh]

Amazingly clear explanation. Thank you.

[@thenomadrhodes]

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

[@BobD1001]

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.

[@rajeshprasad101]

This is indeed very nice. I teach materials science to engineering students and this topic comes there. That's how I stumbled onto your channel. In our lab we do three point bend test on glass slides in a mechanical testing unit. We show that strength increases after etching in HF. After seeing your video I am interested to show this chemical strengthening experiment as this is more realistic than etching in HF. But we do not have the neat kiln you showed. Did you make it yourself? Will ordinary electric furnaces do? Is there any safety concern for furnace/people?

[@rcbowstring123]

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!

[@Brannigan777]

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

[@Qui-9]

What was that word at the end? Amenable or something? Awesome video. To those asking him to test his glass, maybe watch the entire video instead of skipping over stuff. He did it near the beginning.

[@benjaminhamilton2338]

I think it was "amenable to this strengthening process".

[@coriscotupi]

Out of curiosity.. what happened to the potassium nitrate after it cooled to room temperature? Remained liquid? returned to powder? turned solid?

[@coriscotupi]

Applied Science Thanks for replying. BTW thanks also for the incredibly interesting, high quality explanations and demonstrations you provide in so many different areas. Well done!

[@jimmypage3183]

I've worked with auto, residential and commercial glass for several years. Cut , shaped, sanded and more. With that. Yes this very interesting but I have a lot of questions!!!! This needs much more information.

[@rolandjollivet38]

Hi Ben. A few questions; - does your process also increase the surface hardness? Have you done a Rockwell or Vickers test? - if you did this to an existing optical flat, do you think the stresses would make it go out of flat? - it sounds like you let the glass cool quite quickly. Did you not inadvertently temper it too?

[@metrologic5000]

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.

[@o5m1um]

awesome video! Would you be able to tell me if any work can be done later with chemically strengthened glass? I mean like cutting it and etc? Or is it like tempered glass that no work can be done after to it and everything has to be done prior the chemical baths? Thank you

[@adrienperie6119]

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 :)

[@lachezardochev9584]

I want to reproduce this process for a larger detail and in a bigger kiln, that I would prefer not to open through the process. So I have some questions: 1-The melting temperature of KNO3 is 334C and the boiling 400C, what should I do to prevent it from evaporating through the long hold at 450C? Just melt a big enough quantity so there is enough for the bath and enough for evaporation? 2-Any reactions with the surrounding air in the kiln? 3 - I also see it is marked as flammable; any precautions about this? THANKS!

[@rbnhd1976]

Thanks youtube. I've been on KZbin for ten years and I've never seen this video from FIVE FREAKING YEARS AGO. Anyway could the process be applied to a glass fiber optic cable to any benefit?

[@-robo-]

Given what was presented, fiber optic cable would most certainly benefit. The challenge would be in soaking an entire roll. Or perhaps it could go into a long trough bath right as it is formed.

[@-robo-]

The only downside might be a reduction in clarity and thus transmission speed or distance.

[@adk6201]

Very interesting. Do you think annealing of the glass is also significant? I would like to see a control with a slide held at the high temperature but not in potassium salt.

[@Bassillixx]

Experiments on the microscope Cover slides would be my choice of substrate! As would be the use of weight instead of pressure to controllably measure the failure point. After potassium treatment, sputtering with an argon / methane mix would provide interesting results.

[@tntgdh]

Great video and very well explained. Thanks a lot

[@bpark10001]

Glass eyeglass lenses are "chemically tempered" this way. I think the salt used contains silver, and that is what penetrates. Of course, you can also "temper" the glass by slowly heating to a much higher temperature, and quickly cooling in an air blast. It would be interesting to compare the chemical and thermal tempering processes for strength. You should also check the samples with a polariscope.

[@bpark10001]

Have you tried thermal tempering? You heat the glass in an oven to a higher temperature, then quench in an air blast. This is how many eyeglass lenses were tempered. After that, they are tested by dropping a 1" steel ball from 36".

[@josephgauthier5018]

any chance of you posting research papers/patents that reference time and temperature?

[@junak777]

Similar to Prince Rupert. I think of defects as holes. Or... Fixed projected dots, or nucleation as in hail clouds concentric circles, or tape that damp sound, or even spinors( that one is like hail Mary). Also granular surface "derivative" tension..not as same as Chladni. Or simply lightning or even silence in musical chairs, "Kerh's transparent stops" ( Ogdoad ).

[@daniel-q7v3i]

could you tell me some references where I can read more about the chemical strenghening process? Thanks and congratulations for this nice video!

[@Erik_Swiger]

"All glass has tiny defects" When I hear stuff like this, I always think about nanotechnology, and what our common, everyday materials would be like if they were constructed perfectly, with zero defects, down to the atomic level. I hope I live long enough to see us develop these tiny engines of creation.

[@Cormy1]

I have difficulty grasping this as it seems to me the Potassium is equivalent to shoving in a bunch of wedges into the glass, which to me is introducing tension. There will be areas that are compressed, but also areas that will be stretched.

[@ciprianpopa1503]

The medium temperature used must have induced a devitrification too. So the crystalline properties are not exactly similar to the starting glass, thus the effect is not purely chemical.

[@donaldhobson8873]

Especially amenable to chemical strenghening. That's Got to be Lithium, Even smaller atoms. So even more compression when replaced by Potassium.

[@m3sca1]

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

[@gibmebalut]

Did you do a control where you heated the glass without any vapor? I'm interested to see if the heat cycle alone affected the strength of the glass.