Anodizing (Or the beauty of corrosion)

[@SteveGouldinSpain]

My first job circa 1982 was in an architectural metals factory where they anodized aluminum parts for buildings. Popular because the end product was light, easy to shape and provided excellent protection from the elements. If I walk around some part of London now I can still see parts we made on places like the Chelsea Harbour development.

[@FUBARGunpla]

this was a fun watch, when I was roughly 20-21 I used to work in an aluminum anodizing factory and it was one of the few jobs I would go out of my way to learn the science behind because anodizing the multiple ranges of colors and depths we could do really intrigued me. hot dangerous work, but scientifically amazing!

[@thatJoseph]

"Don't do this at home" Me: "Hmmm convince me not to" "This can be lethal" Me: "Hmmmm how much lethal are we talking"

[@thomascrouson6085]

You're welcome for the 69th like. Also, nice comment.

[@thatJoseph]

@@thomascrouson6085 nice 😏

[@sail1999]

I live on a sailboat. After paint failed on some aluminum fittings on the boat, a rigger friend recommended that I black anodize the parts which I did. When I brought the anodized parts to the boatyard, an old timer friend recommended that I coat the parts with lanolin (sheep fat) which I did. The lanolin seals the pores and keeps saltwater out. The anodizing protects the aluminum. More lanolin is re-applied when the parts look a little chalky. It's a little pricey but the anodizers usually charge per batch, not part, so plan accordingly.

[@dougankrum3328]

...boat stuff...you could try 'hard anodizing'....very hard and only available in black....but quite a bit more durable than the regular anodizing.

[@sail1999]

I agree. My goal is less maintenance.

[@gonzos-twin]

have your pieces powdercoated or ceramic coated

[@AtimatikArmy]

Also, stay away from black anodizing as that soaks up the most UV and will ultimately turn brow (unless of course you desire this)...

[@leocurious9919]

"It's a little pricey but the anodizers" And there ends your comment. KZbin... is it _so hard_ so display a few words or what? How can they fail at such simple tasks like showing comments?

[@Motosapien46]

I'd say you met the standard! You never cease to BLOW MY MIND! Your content is what Discovery, TLC and History USED to be! THANK YOU!

[@tihzho]

1:43 This is also the how pearlescent pigments are made. A layer of TO2 is deposited on very small mica (or borosilicate) platelets so the color is produced is by the thickness of the layer. TO2 exists in two crystal types, Anatase and Rutile and they give different results.

[@dougrogan379]

his red shirt was actually made from anodized aluminium. true story

[@DaisukidaioNihon]

dont worry, I believe you, after I saw a rich indian make a golden shirt after gold metal threads, it's possible to create anodized shirts

[@xaraxen]

Indeed, his shirt is actually red [ product ]

[@schmittenhammer]

It is not red, it reflects red.

[@TelekineticKhai]

omg XD

[@kravenslegacy1]

So we're both of his prosthetic eyes

[@iKonakona]

These videos keep getting better and better! I just tell me friends to watch these and they feel smarter! Great job!

[@user-cc32vcg811]

didnt expect you here

[@realdotty5356]

IMAGINE HAVING FRIENDS... yeah... imagine :(

[@RUBIZEN]

Which is why the AR rifles introduced in the mid 50's by Armalite were so advanced. Armalite used manufacturing advances it took from it's parent company, Fairchild aircraft. The anodized aluminum upper receiver is harder than the steel bolt carrier that reciprocates inside it. It's the steel carrier that wears out first.

[@Dr_Xyzt]

Cool! I'll have to take measurements on mine.

[@Rowow]

Except that exactly what makes the rifle a very expensive and ineffective piece of toy. Its nice for sport shooters and consumers, but terrible for the military which requires mass production of cheap yet durable tools.

[@tankolad]

robert karas No, not really. The AR-15 can be cheap if you want a cheap one. The anodized aluminium receiver isn't the source of failures or low accuracy in cheap rifles, or in expensive rifles, or in any rifles. The smaller parts that require high precision tools to manufacture typically fail long before the receiver. From an engineering standpoint, the AR-15's receiver is excellent: it's durable because of the anodization process, rigid because it has relatively thick walls and still lightweight because it's made from aluminium.

[@rogertycholiz2218]

Smith & Wesson made model 39 semi auto with an anodized frame around 1950.

[@testy462]

robert karas yeah, so terrible the most effective and powerful military in the world has been using it for what, 50+ years?

[@artiet5982]

I have always loved anodizing- racing BMX bicycles as a kid the coolest looking parts were anodized. I've always wondered how the process was completed and have even tried to find other videos to explain so I could try to accomplish myself. This video is fantastic. Thanks for posting! Don't know if I can pull the process off myself though.

[@ano_nym]

Throw a BMX frame into the bathtub with attached wires, stand back and connect it to the mains. What could go wrong.

[@enja001]

all rust is oxidation but not all oxidation is rust

[@sadcatman1057]

dion759 i thought rust was a bunch of naked people running around killing eachother

[@kipve]

+Sponge Boob also an unfinished game

[@rjserra2489]

While it is true that rust is the oxide of iron, you need to remember that Bill is talking to the masses. The masses are not into the finer points of corrosion. Bill is just trying to get a concept across in a short video. So, try to cut him a little slack and let that slide even though it grates on your more precise tendencies.

[@thewhitemustang]

Yes, most people don't know what oxidation is, but everyone knows what rust is. This could cause future confusion with people that are really trying to learn how things work. It would've been better to say "it's similar to rust" or "sort of like rust". This isn't a criticism, I love Bill's videos.

[@melgross]

Actually, that’s not quite true guys. While the term is mostly used for iron and steel corrosion, rust is often used to describe similar action on other metal surfaces. Look it up, and don’t make assumptions.

[@neogeon]

As an interesting note: Type III aluminum anodizing (sometimes called "hard coat") has a surface hardness similar to steel. With Type III hardcoat, you can have the weight, rust-free nature, and cost of aluminum matched with the hardness of steel. While this doesn't have much use from a structure perspective, it works great for sliding pieces as the finish will not wear off easily like bare aluminum or Type II anodizing (standard anodizing) or show scratches from normal use.

[@endimion17]

You carry on where popular TV shows came to a halt almost 20 years ago, replacing things like this with cheap and revolting persuasion techniques like ridiculously deep voices, extatic screaming and camera shaking describing what is essentially bad science. This is awesome. Keep up the good work.

[@FirmCat]

Many, many years ago, I worked at a company that made photosensitive plates for printers. They took huge reels of aluminium of varying thickness, pulled them through a 30 yard long bath and used huge currents to anodize the material. Controling the speed and current controlled the thickness of the oxide layer. It was then coated with a photo sensative layer. After exposure and developing the plates, the pores that were not closed by the remaining photo sensative layer take up and release the ink on the paper. Clever stuff.

[@davep323]

The music makes me want to play the sims

[@GregoryTheGr8ster]

Good one! The Sims had such fitting music.

[@naayu.aaminah]

woah

[@NJP76]

You are sooo right! And I thought I was the only one. As soon as the video started, I started thinking, "Hmm, I haven't played Sims for some time." (Starting the Sims...)

[@Wailwulf]

I went on a field trip to a plant that anodized aluminium. The plant was very professional to the point that everything was clean, so clean that their vats of acid was crystal clear to the bottom of their four foot depth. It was like looking at pools of clear, cold water, and to my dismay I felt an urge to put my hand in there, luckily my fore brain kept control and I took the idea of working at such a place off the list.

[@trublgrl]

I've noticed anodizing is used in cookware. I'd love to see Bill present the different surface engineering of cooking materials to explain their different properties.

[@kinbolluck476]

😮

[@49metal]

How does "boiling the aluminum in hot water" "seal" the layer? Glossing over that is bad form.

[@puncheex2]

Hardens the resin in the dye. Causes oxidation of any flaws in the aluminum surface.

[@itsmeian17]

After seeing the last video he released, I bought his book, and really enjoyed it. Recommend others do the same, many more interesting stories, and things to learn about our everyday life.

[@Dartheomus]

As a chemist, I really didn't expect to learn a whole lot when I clicked on your video. I was wrong!!!! :) Thanks so much. It's so rare to find videos that talk about science in such a concise yet useful way.

[@ChrisWunsch]

Yet another amazing video Bill. Thank you very much for all of your work! I look forward to my book arriving tomorrow!

[@MrMustacrackish]

1:35 I was a welder for 5 years and I always loved the beautiful colors when joining Stainless Steel. Now the dummy answer they give us when teaching TIG welding is it's oxidizing (despite the argon shielding gas we use to prevent oxidation and the nickel and chromium). It follows the same pattern of a light hay color through the red blues and purples. Can I make an assumption about how much penetration I am getting based on the color of the weld? Is this the more detailed answer of what is happening? I don't have a ton of experience welding Aluminum but I have done it a handful of times. However I have never seen the color change on aluminum. The procedure is much different we use AC current and a pure tungsten electrode that we intentionally ball up instead of sharpen to a point.

[@andy0422]

I used to work at an plating company doing aluminum anodizing. There were two types of anodizing they did, soft and hardcoat. Two different processes. Only soft anodizing will accept the dyes. Hard anodizing would be either natural which are different shades of brown or dyed black. Bill explained it better than my former boss. Bill, do a hard anodize episode for your fans.

[@WeighedWilson]

I remember black being the only option for hard anodizing.

[@zacharywormwood3476]

I'm a teacher, my students text was brief on electrochemical processes. This is an excellent resource. Thank you.

[@MegaDataRecovery]

The engineerguy would make an outstanding teacher. Great video's. I have my kids watch them.

[@calebellingson8860]

I'm pretty sure he's a professor at a college.

[@SphinCorp]

Just bought your book! Thank you for being awesome - A perpetually curious software engineer

[@unnati_hulke]

Been 11 years since released, the video still keeps me satisfied with the accurate information I wanted

[@TelekineticKhai]

So that's the deal with all this "anodized' craze - thanks for the very good explanation!

[@NuclearRoll]

I love the way this man speaks, often modern science videos have a "whhoaaduude" tone to them and don't really get the point. His videos are quite the long due throw back to the informative, straight forward, information videos you see from the 1940s-1970s. Really refreshing.

[@engineerguyvideo]

That is the ethos I am aiming for. Of course I fee up on ascent of man, cosmos etc. I have never been too interested in doing US TV in its current incarnation: it isn't designed for anyone to pay attention to!

[@NuclearRoll]

engineerguy Wow, and you're active in the comments. You're doing something that's very needed and in short supply, I'm buying your book as soon as I get paid. Thank you for all thay you do :)

[@LoveStance]

Exceptional video. it told me exactly what I wanted to know regarding WHAT anodizing was, but what to expect. Thanks for for such a complete, and easy to understand explanation!

[@markroberts7759]

Not all aluminum parts should anodized, If a part is under cyclical stress it may fail in less time due to the affect on the surface. micro fractures will occur from the the altered surface. Thinking of aircraft components.

[@MrAluminox]

And boats. Yes it's true on thin aluminium, not on thick pieces as the ratio layer thickness on piece thickness gets smaller and amaller. The main problem is how to control the galvanic effet on a big complex piece to get a uniform thickness of anodization. And secondary problem cost and lack of durability of a soft anodization.

[@christopheryee4850]

How thin would be not ok

[@malcontent7976]

@@christopheryee4850 one third of an inch

[@joytech23]

Just subscribed last night, and a new video comes out? I love this channel so much.. Mainly the host who happens to somehow make everything understandable and entertaining. lol

[@AlojzyZyrokompas]

I love those videos. Wish there were more of them coming.

[@Kerrigan1000]

This video has sealed the deal, I'm going to get the book. ....done. I do cold metal casting of resins. I have a silicone mold of an item. I will sometimes brush in powdered aluminum to the mold so that the liquid resin will grab that and have an aluminum coating that is bound to the outside layer of the resin. From there I can use some steel wool and give it a very real brushed metal look. This video makes me wonder if I could try and anodize it at all. I'm not sure but to have a colored aluminum finish would be great for the decorative pieces I cast.

[@spugintrntl]

+Jason Parker I would buy the book, but then I wouldn't be able to hear his soothing voice paired with the quirky music.

[@bluefernlove]

You don't want to anodize that because it's not pure metal. The resin might produce a nasty reaction. You could try just coloring the aluminium powder with alcohol dye, let it evaporate completely and then coat your mold with that powder.

[@brendenfullmer1052]

Ive been trying to learn how to anodize aluminum but the sources I've been looking at have all said something different, what do I do?

[@SykeMediaTV]

Wish I had this chap as my science teacher ... mine just shouted at me a lot and made me cry!

[@jiberish001]

I wish I had known about this channel sooner. These are great.

[@N3rdyDav3]

These videos change the way I look at the world. I look forward to many many more in the future.

[@YourCitizen]

Why was I recommended this 8 years later? Either way, good video.

[@engineerguyvideo]

because itbis perennial

[@LazyScoutJace]

I remember learning about this in Electrochemistry. I remember telling my best friend about this fascination and she just dozed off! XD

[@ctempleton3]

One thing that is interesting to note is that anodizing and alodining (a similar chromate conversion process) are the basis of corrosion resistance used on all aluminum aircraft.

[@4Gehe2]

To give an idea how fast the oxidation effect is. When we weld aluminium and we brush the oxide layer we have bit less than 10 minutes to weld or we need to brush it again.

[@marcuscoster6529]

So since certain colors are a thicker layer of oxide, those colors are more durable than the others?

[@the_eminent_Joshua_E_Hrouda]

Fascinating!! Well explained!! Can you anodize copper, or tin to change it's colour??? (I'd like to make a rainbow PCB!)

[@MrAluminox]

By anodization no. Tin there is nothing to do. Copper by controlled heating and cooling like some steels or oxidation by chemicals. There are plenty on infons in Internet.

[@TheMohawkNinja]

I've actually been wanting to anodize a piece of aluminum that I own. Doesn't seem like it should be that difficult. I just need to figure out what the correct dye to use is, and what will be the safest and most efficient way to put the electricity into the metal.

[@Milkmans_Son]

As you probably know by now, it's not the electricity you need to worry about messing with, it's the "solution".

[@rockapedra1130]

Nice video but a small correction: with aluminum the current doesn’t “push” into the aluminum to make channels, the process is actually chemical. What’s missing here is that you anodize in an acid, typically diluted sulfuric acid. The anodizing process is a tug of war between the acid that keeps digging holes and the current that keeps forming oxide. Where the acid is winning, you get the long empty tubes, where the current is winning, you get the oxide walls. Without enough acid, you never get past the nanometer thin barrier layer. Without enough current, the acid eats away all the oxide. Keeping everything balanced is the hard part. Love your channel!

[@bunkafashioncollege]

Love these videos. Too bad you took out the humor of the first year - that made the videos not only informative, but also entertaining.

[@0MVR_0]

I will not lie to you Bill. Sometimes I click for the music.

[@shravanbhat7389]

Such a shame these talented guys don't post they awesome videos anymore

[@engineerguyvideo]

I will: see Engineerguy.com … just finished book, video series to go with it.

[@GrandHighGamer]

It seems strange to focus on the colours created by anodising if the main colour in a finished product is just by dye added. Surely the colour of the corrosion then becomes superfluous since it is masked by whatever dye is used?

[@bradleymorrison]

Why does this guy remind me of Luke Skywalker?

[@engineerguyvideo]

+Brad M I am Luke Skywalker ... I cannot make enough money with voice overs for batsman cartoons so I have to make these videos too.

[@bradleymorrison]

Hey engineerguy! hahah love the videos!

[@engineerguyvideo]

+Brad M thank you!

[@Phelan666]

He killed his own father?

[@gavins7542]

Because u prolly want to see him in a lightsaber fight against bill nye.

[@NoogahOogah]

This is really cool. You are simultaneously educating us on a fascinating topic, while earning a lot of free advertising for your book. I was forwarded here from a tech blog, who I doubt has any affiliation with you.

[@dksarkar]

Dear Bill, your video is very fascinating and easy to understand for students as well as professors. I find it yesterday and going to show my student today in the course of surface engineering at UQAC. I am running a project on anodization of aluminum but use cathode in the same acidic bath. However, in your video I did not understand where did you put the cathode? Secondly, can you find a condition (playing with thickness as well as metals) that your anodized layer hence the whole material become invisible? ha ha ha!!!

[@tennicktenstyl]

"durable" and hinges attach to paper-thin sheet of aluminum instead to rigid case.

[@MewK_]

The book is really nicely written, you should check it out. Of course there is an e-book version if you don't like dead tree.

[@allmycircuits8850]

It could be worth mentioning that anodized aluminium is used not just for aesthetic purposes (different colors which don't wear so easily) but also to increase heat radiation from surface. 'Clean' aluminium is so bad in emitting IR, so the only way it can lose heat is through convection. Not bad if there is some fan attached. But if you expect your surface to be a passive heatsink, there is great advantage to make the surface black in IR region. The best way to do it with aluminium is to anodize it. You can see a lot of dark aluminium heatsinks which are anodized exactly for that.

[@kahlzun]

Does that still work after the dye is applied?

[@allmycircuits8850]

Yes. Almost any dye is 'black' in thermal infrared range. For example, centralized heating radiators made of aluminum are almost always of white color, but in IR they are black, so they emit pretty well. Another example is International Space Station heatsinks: they are also white, but of course they emit very well, it's the only way to get rid of heat in vacuum of space! And they are white because this way Sun can't heat them!

[@kahlzun]

+AllMyCircuits did not know that! Cool.

[@yon2004]

Oh another great video, Just about to read this chapter tonight.

[@bbblaesing]

Coincidentally I will be working as an Anodizing intern for Apple this summer, cool stuff!

[@missingno2401]

and if you stick a fork in the positive terminal of a power socket (has to be titanium or aluminum), pour water on top, you can anodize the fork and turn it different colors.

[@Sillimant_]

this sounds like suicide

[@missingno2401]

@@Sillimant_ is suicide if you stick another one in and hold both of them with different hands

[@Truthiness231]

One of the best videos you guys have done so far, and I MUST have that book! ^.^

[@jimburnsjr.]

Beautiful Video... Thank you very much for posting, would like to have that book.

[@user-ki2ow7if5c]

Your latest video dates fro a year ago. Why have you stopped doing those nice videos?

[@brtnspn]

Thank God they are still working on new stuff! As this video they posted on vimeo demonstrates: vimeo.com/89656135 They are working on some kind of a clock or automaton or something with a series of gears in it.

[@georgeb.wolffsohn30]

What do you use to add color ? How do you control the specific hue and value ?

[@robi8020]

Short, sweet, and informative! Thanks!

[@TheSHJGaming]

Is this oxide layer similar to tempering steel, where you get colours from light straw to purple?

[@antonhelsgaun]

SHJ Gaming yes

[@dapper189]

What are your thoughts on anodizing vs powder coating?

[@sguan17]

+Joe Schmoe powder coating creates a rougher surface than anodizing

[@dapper189]

+Steven Guan thank you.

[@sguan17]

powder coating is more corrosion resistant especially in the salt air environment while anodizing is more wear resistant where scratches are expected. that's one of the reason why personal electronic products are anodized.

[@dapper189]

Oh. I think in terms of car parts. I live In central hellinois. Prime rust belt area. Thanks for sorting that out.

[@BigAdam2050]

Is this a similar way that metal on exhausts turns blue or goldish with time and heat?

[@imgod22222]

I wish you would've taken a pair of calipers (micrometer) to measure (any one) dimension(s) of the Ti strip before and after the anodizing, so we at home could in fact see that there is something being added. Otherwise, phenomenal video. I tip my hat off to you.

[@shodanxx]

What voltage & current profiles are needed to create hard anodize on aluminium ?

[@Poke493]

So if anodized colors can't come off besides scraping the aluminum, how come the black iPhone 5 had the black color wear off?

[@krovek]

i know its nitpicking and you are just making a comparison, but I snarked when referring to aluminum oxide as rust.

[@ThePeterDislikeShow]

Can tin or pewter be anodized?

[@scottk7613]

I want to make a aluminum sword, with 2 diffrent colors. The blade and the handle. I want to know, how do i do this the right way, without bleeding the colors into each ends. Do i just tape up the end im not dipping yet, with maybe duct tap. Then dunk it in boiling water for maybe 10 min, then duct tap the other end and repeat the same thing. Will the color pass the water line at all? Does it lose color when i put it in boiling water? Thanks

[@tryhardofdoom7682]

Can someone please explain me the colour part again? I understand that there probably has to be a phase difference between light bouncing of the Titanium-Oxide vs the Titanium, since some of the light travels deeper into the material and therefor needs longer to come out again. I too understand that two waves with the same wavelength but in 180° phase cancel each other out. But how does this correlate with the colour of the different oxidization depth? Does the different thickness of Titanium-Oxide lead to a change of the absorption of white light? And how do I fit the cancelling interferance into there? And why is there excactly the 180° phase difference and not any other? This just doesn't seem to make any sense to me, please send help :(

[@hart-of-gold]

The thickness of the oxide layer changes the small range of wavelengths that are cancelled out by destructive interference. As white light contains all visible wavelengths (assuming a true white light, most floroesent lights are not true white). The colour seen is the compulment of the colour absorbed, that is, all other wavelengths are reflected.

[@andrewstamford1988]

So putting it very basically, ignoring specific steps and materials, you run a current through the metal you want anodized, which 'primes' the metal with a coating that is ready to accept a dye to intensify the color and finally, the finish is sealed by boiling the piece to lock in that color? I don't know why, but 20 years ago I missed a program on Discovery Channel, and never tried to find out, but it kept gnawing at me to figure out why things like carabiners came in various colors. Now, 20 years later, I can sleep well knowing how it's done. Bless you Bill - my sanity is partially saved! 🙏

[@jerredscott]

What voltage and amperage would be needed for a proper power source, to anodize Titanium?

[@tryhardofdoom7682]

I think one can calculate that using the cell potential table and stuff? I don't know how though :( And on top of this voltage required for oxidizing and reducing you need to add some (idk how high) amount of voltage to overcome the inhibiting effect of the charged layers of water formed near the electrode? Sorry for this vague answer :(

[@MrAluminox]

You have the answer in the video...look a the source of power, it says all...

[@impsick]

Awesome i always wondered how they anodized aluminium. So you mentioned the two wave lengths of light cancel out. Ive always wondered if it would be possible to totally phase out 2 light beams. lol i wonder...

[@costaowens]

I would love to meet this guy, he seems so interesting and knowledgable. I would love to meet him.

[@curtcoffee]

What is the HP power supply model number?

[@shaihuld]

Just one of the most awesome channel on youtube, KEEP UP !! :)

[@michaelhtvr]

Excellent explanation.

[@nickdibart]

I sincerely miss these videos...

[@unclefungus7395]

I absolutely love your channel

[@VarunSainiKumar]

Awesome work...something to learn from every video..keep up the good work.

[@millenniumzeek]

Excellent explanation

[@SimpleJimmyBlueChip]

how are iridescent anno jobs done like the ones on some custom paintball guns

[@obi-wankenobi9871]

So colour anodizing is basically a coloured kashima coat?

[@gulllars]

Great video. It would be nice to hear a bit about the cost of the process though, but i guess that's outside the scope of this channel.

[@terrikhat2]

Is there any way I could download/purchase a copy of this video clip?

[@s.bhatta5115]

Creative video to understand engineering concepts

[@yeahthatsright33]

incredible video. This was perfect, thank you!

[@CampKohler]

Wonderful red anodizing job on your shirt!

[@krisel5780]

Hello Everyone, I have a problem with anodising the pressure casting aluminium, means the alloy with high silicon contain (Si>6%). Does anybody tried this? Which parameter could be a problem, which should be combined?

[@Ebonyzer]

That's great and all, but will it blend?

[@umangu]

Excellent video!

[@kcsnipes]

Appreciate that informative presentation 👍

[@Zixzi104]

Is this the same stuff the HTC One S is made of?

[@ximenoworks]

What about Alodine/iridite on ALU?

[@dimesonhiseyes9134]

you can actually do this at home with a fairly cheap welder and the right chemicals. I think I used to use sulfuric acid when I did paintball gun parts like 15 years ago.

[@TheAllBlackMan]

Is this a similar process to blued steel?

[@korakys]

+TheAllBlackMan No, that is typically done by dipping the steel in a hot chemical bath.

[@TheAllBlackMan]

circ1ebreaker I was more thinking in terms of what happens to the metal itself.

[@kaje01]

+TheAllBlackMan I don't think so. I used to work in manufacturing, so I've seen a lot of metal get hot. Steel changes color and hardness when heated, it also loses it's memory. So I think it's more of structural thing

[@molinobeer]

yes blueing steel is an oxidation process.