Posted on 02/06/2016 8:20:33 PM PST by Utilizer
Anodizing (Or the beauty of corrosion) Bill describes how metals like aluminum and titanium are made resistant to corrosion by growing an oxide layer into the metals. These is the same process used on many Apple products.
I read somewhere that pure iron does the same thing.
The reason it rusts is the impurities which are almost always in it.
Man ... did YOU get all screwed up by that Republican intro !
Interesting video. I’ve always heard about anodized surfaces, but didn’t know what it was.
Some of those impurities are the reason “Damascus Steel” was so highly prized in times gone by. So a good look at this process is most informative, as it might conceivably be transferred to other areas.
Well, and besides the fact that I look forward to using this quite soon to certain projects I have in mind as I develop more constructs...
Certainly better-looking ones, at the very least. :)
Eugene Stoner’s anodized alum. Receiver.Yayyyy!
It’s a commie killing wonder gun.
Being a recovering aircraft engineer I have seen a lot of anodizing parts in my day. Neat stuff. But in a big metal finishing shop you don’t want to see how the sausage is made. The conditions are quite unpleasant.
Ehrmmm... Whatever you say, mate. *cocks eyebrow* *concerned expression* *wary glance*
Neither did I. But I thought not only was the video fascinating, the other links to more information concerning the process were quite informative, and I look forward to possibly implementing some of what is shown there to some projects I have currently in process.
At the very least it must lead to longer-lasting projects (at least externally) when all is said and done. :) _ One would hope, at least.
If kids were taught this way I think we’d have a heck of a lot more engineers
DAMASCUS STEEL is made by folding and hammering layers of steel into a single blade or tool. The hammering and layering give it the properties of forged steel but since it is a layered steel it does not fracture as a single crystalline unit. It was quite advanced metallurgy in its time. It is also a very beautiful product.
Been around for many decades in aerospace and car racing parts.
Trying to make it sound like some sort of apple innovation is pathetic. I was buying anodized hydraulic fittings forty years ago for hobby stuff.
Damascus Steel is not simply a product of simple Iron ore being forged and re-forged over and over again in layers, it is created by a blend if iron ore with a mix of carbon and other impurities smelted at the same time that gave it its unique qualities and made it so treasured for those that worked with it.
Sadly, the exact nature of how it came to be created has been lost over time, but along with it being forged with simple bellows systems (increased oxygen) and carbon introduced during the smelting process (along with certain trace elements present with the ores when they were mined at the time) the completed product was so well-renowned that its name is still recognized hundreds of years after the secret of its manufacture has been lost to the annals of time.
Notably, the trace elements and additional oxidation introduced during the forging process produced a result much like the anodization of aluminum that this thread addresses. Instead of something brittle that was a plague upon the swords and other edged blades of the time, the forging process on the unique combination of ores and minor impurities associated with it produced something much more durable and usable when the process was completed.
https://m.youtube.com/watch?v=eX2_Szx3vA0
Steviebar showing how he makes pattern welded billets for later forging.
Pinging dayglored, Shadow Ace, and ThunderSleeps because it's not just Apple that uses this technique.
The latest Apple/Mac/iOS Pings can be found by searching Keyword "ApplePingList" on FreeRepublic's Search.
If you want on or off the Mac Ping List, Freepmail me
The secret of Damascus Swords was in the fact of how their metal was made. . . The hammer welding of iron wire with repeated reheating in a charcoal forge had the effect of incorporating minute amounts of carbon in the iron with the iron wires that were hammer welded. As you may know, carbon added to iron alloys makes steel, which was much stronger than the iron blades of other techniques of the time. Too much reheating and hammering and the blade became brittle, to little and it was no better than iron, wouldn't take and hold an edge, and would fail. The secret was knowing when to stop, when enough had been done for each sword. The wires were welded together by both forging at low temperature and the physical force of the hammering. It made a ply type laminate structure as well of stronger and springier steel.
The appearance of the Damascene metal was unique due to the patterns of each swordsmith's style of curling the wires.
Unfortunately, the system also incorporated impururities which resulted in the failure modes of the metal as it aged. . . Points of oxidation would form and crystallization of the metal weakening the blade over time and flexation causing them to go brittle with age. This is the same problem that makes Damascus barrel shotguns inherently unsafe no matter how good the barrel looks on the outside, it may be too brittle on the inside to handle even weak loads because age and internal corrosion has taken a toll.
The only better system for making swords was that of the Japanese who better understood the physics of the process and the nature of the sword metals with the number of folds they had given each incorporating various amounts of charcoal in each. The very best would have seven different types of steel in the blade. I have a Tanto (short blade dagger or sword) in my collection which was made by one of the finest swordsmiths in Japan who founded a major school or style of sword making. He was last known to be making swords in 1060 AD, so my blade is over a thousand years old.
The swordsmith was so pleased with the blade when he finished it he signed it. What's more, he went on and commented on the tang, saying "On a good day in late summer," which means he was very pleased with the blade and essentially named it.
Forty some years ago, a Japanese appraiser valued it at over $50,000. It's not much to look at, it's in a plain bamboo case, but some of the rainbow case hardening colors are still on the blade to this day, and it's still razor sharp. You cannot touch the blade with bare fingers or it will turn black with rust where ever your fingers touched if not cleaned immediately.
The Japanese appraiser suggested I have it polished in Japan by one of their "Living National Treasures," a man who still made Samurai swords in the ancient techniques. He'd only charge me about $500 an inch or so to do it, but it would bring out the brilliant colors of the rainbow that are still there. He does it with talcum powder as an abrasive and spends about a day working on each inch per side. . .
But, the appraiser warned me, once the blade arrives in Japan, it can never be returned under Japanese law! I'd be permitted to continue to own it, but I'd be required to place it on permanent loan to a Japanese cultural heritage organization of my choice in Japan. . . but polishing it, he assured me, would instantly double or maybe even triple its value! Whoopie duck. I declined.
A relatively boring technical video about anodizing
THAT'S what I meant.
That’s some amazing information! And quite an artifact you have!
I’d read in places about how some hero’s sword “broke” and wondered how that could happen. Now I know: poorly made and kept blades will certainly break thanks to inherent and introduced weaknesses. But even great ones can become brittle with time.
Facinating. Great comment.
I once worked in the quality control department of a factory. There were all kinds of interesting tools for testing different things. One of them was to electronically test the thickness of anodizing. We had a lot of tools that would measure to 0.001”, but the anodizing tool divided each 0.001” one-thousand times. It measured how many millionths of an inch the anodizing was. We call them “mils” (for millionths) even though that was not technically correct.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.