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The Sexiest Metal
jonerik writes "Denver's weekly Westword magazine has this article on titanium and the attempts to break it out of its traditional aerospace/defense industry niche, including its growing use in architecture, computers, jewelry, sports, knives, cars, medicine, and other areas. The upside: It's as strong as steel but weighs half as much, it doesn't rust, and it's fairly plentiful. The downside: It's expensive compared to steel and aluminum and its high melting point makes it difficult to work with under some conditions. Still, it's nice to see it being used in other applications." Heck, I know someone who used it as his wedding ring. Pretty cool, actually.
Watches are some of the most common consumer goods available in titanium. Citizen is the largest titanium watch maker in the world.
A concern with titanium watches is that, while they're light and strong, they also tend to scratch more easily than steel. This is a concern because in time a titanium watch will look more battered than a stainless steel one. Citizen actually claims to have a process to reduce titanium's "softness" (can't recall if it's an alloy or a special coating), thus reducing this problem.
My wife and I got married back on March 24, and we are both wearing excellent titanium rings from www.boonerings.com.
My ring is styled after Ed Harris's ring from The Abyss, and my wife has a pair of helix rings, one that holds a diamond through tension in a spectacular manner not possible with softer metals.
See: http://www.boonerings.com/large/helixxlite.htm
In regards to safety, Titanium rings can be easilly removed using cutting tools present in most ERs.
Considering that titanium has been used in mountainbike frames for at least 8 years, and in quite a thin layer, especially compared to the steel/cro-mo frames, and have proven themselves to be just as durable, you are quite wrong. I used to compete in mountainbiking, and I had a titanium frame. Me and another biker smashed into a rock at about 45km/h, with our bikes hitting the rock instead of us hitting it, and his alu 8005 frame got warped, his upper tube bending, while my titanium frame barely got scratched.
Titanium is actually a very reactive metal even more so than Iron.
Fe = -.440
Ti= -1.63
Titaniums corrosion resistance is actually confered to it by the formation of titanium dioxide scales, TiO2 (same stuff in toothpastes go ahead look), the layer slows down the diffusion of oxygen and other oxideizers to the surface of the metal. Much like Chromium does in stainless steel (Cr2O3).
Is Titanium then the best metal for all corrosive environments? Hell no! Its protection is based on the thermodynamic stability of its scales.
Put your nice shiny new Titanium in a highly oxidizing and basic environment (look up Pourbaix diagrams if you want more info). Kiss it goodbye. While plain carbon steel would have resisted it since its scales are stable in that environment and a lot cheaper to. Had you used titanium for your reactor thinking it was the best, you my friend would have been fired.
The moral of the story, there is no one good metal for all applications. You need to consider many factors not to least mention cost.
Veramocor
The newer TiBooks are reinforced in order to prevent this bending problem. The first few runs of them (including my own) flop around to a dangerous degree unless you make sure to pick them up with both hands. If a CD or DVD's in its drive, you can hear it getting scuffed up by the drive hardware when it bends! Apple's "designer" computers have a history of problems in the first run (heat fissures in the plastic moulding of the G4 cubes come to mind). Be glad you weren't an early adopter :)
"The problem with the French is that they don't have a word for 'entrepeneur'." -George W. Bush
For most applications it is Titanium 6-4, very hard and very tough:
- 6% aluminum
- 4% vanadium
- 90% titanium
For bicycle frames, Titanium 3-2.5 is used as it is more ductile (for forming seamless tubes) and has a better stiffness in torsion (which is needed as pushing on one peddle then the other torques the frame back and forth):
- 3% aluminum
- 2.5% vanadium
- 94.5% pure titanium
It took an injury to my left hand with a circular saw -- and a nurse who pulled the ring off while I was unconscious -- so that they could put about 10 stitches in that finger (not counting the 70 or so inside and out on my index and middle fingers) to convince me that Ti Wedding rings are *NOT* a good idea.
...Open Source isn't the only answer -- but it's almost always a better value than the alternatives...
Check out the movies. Now THAT'S sexy!
;-)
Some more Titanium info, but this site is just way sexy. Check out the Flash Periodic Table on it.
Remember this post? "The Periodic Table of Comic Book Elements" from 2 days ago. The main site seems to have been fatally slashdotted, but here's Titanium on a mirror. Not so sexy, but timely.
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
Hmm... It depends on the alloy.
"3/2" Ti alloy is what is usually used in bike tubes, unless it's a Lightspeed, which uses "6/4" alloy in some of its frames.
The Ti alloy for glasses is an alloy that doesn't stay bent.
And the Ti tubes in bike frames, especially road bikes, can be breathtakingly thin. Cycle Sport recently did an article on a bike that the downtube was almost as thin as a soda can, in the middle (the ends are internally butted, i.e, thicker), and flexible (i.e, you could push it in with your hand...). And the fitted out bike weighed 15 lbs, with all the lightest weight stuff they could put on it.
Bike frames are insane compared with where they were 10 or even 5 years ago, thanks to Cannondale, Trek, Kestrel, Klein, Lightspeed and Merlin, et al., not only with newer steel alloys, but also with the newer aluminum alloys, titanium, and carbon fiber.
I remember reading in Science News a few months back that a new process for reclaiming Ti from oxide compounds was discovered. Ti is one of the more abundant elements on the planet, but most of it is in a form that makes it unusable for metal products. The article predicted that it would be used for all sorts of things very soon (like car frames).
Puts materials scientist hat on
The TiBook is made from commertially-pure (CP) Titanium. This is basically an unalloyed grade and is very weak relative to the better 6-4 (6%Al-4%V) "aircraft grade" Titanium alloys.
This is the thing. Apple chose Titanium more because it was sexy than anything else. You see a lot of things advertised as "Titanium", and often times the Titanium plays no important role in the product. There are some golf balls out there that has some Titanium in one of the resins close to the core, but the Ti is not in metal form, and is really only there in minute quantities.
In fact, sometimes titanium overshadows everything else there. One of the responses mentions "Titanium" glasses frames that are very flexible. Those are not pure titanium. They are a 50-50 alloy of Titanium and Nickel. It is a "shape-memory alloy" which has the ability to deform easily by realigning the crystal structure when bent! and then shifting the crystal structure back when the stress is removed. They are way cooler than just titanium. They have been precision engineered to be superelastic.
Titanium may be sexy, but it is not always the whole story. The marketing people often latch on to it, but as it becomes more common (and it will), it will start to lose it's allure. A large part of the cost of titanium is in refining it from the ore, and I've heard about a few developments that might bring it closer to the cost of aluminum in that respect.
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The internet is the greatest source of biased information in the history of mankind.
Kitchen sinks, stoves, refrigerator, bath tubs, many have a porcelain coating and rutile is the whiteness in the coating. Even your green stove has a white rutile base prior to adding green pigment.
That being said, I agree that structurally, it would have been better to use steel or alluminum for the case of the PowerBook. However I own a powerBook, and, although flexible, I prefer it's titanium, although polished aluminum would be cool too.
The coolest thing about titanium, that often get's looked over is its resiliancy. It makes it ideal for applications where steel and aluminum are useless. Look at bicycle frames, for example. Steel frames have been around for years and they have been optimized to be ultralight, strong, yet flexible enough for a comfortable ride. Aluminum came along, and although lighter than steel, it made for a rigid stiff frame and a toothshattering bike ride. The *design* of the aluminum frames could have been altered to allow for more resiliency, but the problem with aluminum is it fatigues and breaks if it flexes to much, so redesigning the frame to be more flexible was out of the question. Fortuneatly, suspension bicycles need a high stiffness in order to keep hinges/shocks/etc. lined up straight, so aluminum is ideal for this purpose.
Titanium, although not as strong as steel and not as light as aluminum, offers resilience. The first Ti mountain bike frames were awful, built similar to their steel counterparts, and compared to riding a wet-noodle rather than a bicycle. Over the years, the design of Ti bikes has caught so that the frames are resilient in all of the right places, while still remaining sturdy in the other places. Some frames have even used this resilience as the suspension and put a damper/shock into the frame to allow for suspension travel and damping in a metal frame with NO hinges.
As a proud Palmares owner and CAT-3, I will testify that the Litespeed frames are worth every penny more than their Ti brothers. Unfortunately, stiffness is something that they've only lately started to figure out. The newer ones this year have carbon rear triangles and are stiff enough to seriously consider racing on. Something else of note, nicks in the frame need to be polished and grinded out as Ti can become brittle around them and eventually fail, although I've never heard of it happening to a bike. I own 3 high end bikes, 2 Al and 1 Ti and the Ti is becoming my favorite it's even starting to outclass the Pinarello Prince that I love so so so so much. I can ride that thing for 8 hours and ride again the next day, on Al I can jump a lot better but 5 hours on the bike and I'm hurting for a day or two after feeling every little crack and pebble in the road. Great for training on, for now I'll still race Al, that may change though.
For some time now people have been arguing the relative benefits of different bike materials. For most of bike history it was steel, but steel's heavy, plus it rusts. You're lucky to get a steel frame under 5 pounds. Some people still swear by the loose feel of a steel bike, but steel is on its way out. Because it's so damn heavy you can't make a really stiff bike from steel - tube stiffness squares as diameter doubles.
For pro-level racing, steel is out, no question. When you're trying to put as much energy from each peddle stroke in to forward movement and speed, any flex is out, for that matter Ti is out too. The only people who race it are the people who aren't quite good enough to go pro but are racing 30+ races a year and can't afford to replace their bike every few months or year. For general purpose riding steel is going through a renewal. The air cooled steels that they are making now are as a light as Al but they have the ride of steel, Reynolds and Dedacci are making wicked awesome steels. If you're in to touring or putting serious milage on steel is one hell of a bike. Check out the LeMond Zurich, for example, in its price range is as fine a bike as you'll find, weighs in right around a similarly equipped Al bike. All of the greats still have steel offerings also, Colnago, Pegoretti, Pinarello, Bianchi, and just about all American custom shops do it. I think in the land of Trek, Cannondale, and Specialized steel is disappearing because they have to have Al facilities to build mountain bikes and so they want to support only one metal. Steel is here for the long haul though, I'd have a hard time recommending that a lot of people buy a $5000 Litespeed because they want to "get back in to riding" The lower echelon Ti frames are like wet noodles and dollar for dollar you can get a much better steel frame. Also, steel is "springy" not loose.
Carbon fiber has gotten big lately, too. Tell me this [kestrel-usa.com] doesn't make your mouth water. That's right - it's got no seat tube. No way can you do that with any metal. Carbon's frighteningly light, but fragile - little scratches really build up and can adversly affect the frame. If you T-bone a carbon bike, one of two things will happen: (a) nothing, (b) you're walking home carrying $2,500 worth of plastic. Trek makes a lot of carbon bikes, including the one [trekbikes.com] Lance Armstrong has been dominating the Tour with. That frame weighs 2.25 pounds.
Trouble is, the start-up cost for a carbon bike fab is astronomical - higher than any other material. If you want a custom frame, you're likely SOL. This is where Ti shines - custom frames are almost as easy as steel.
Plus most carbons are kind of "woody" feeling. It's not like riding a soft frame, they can be stiffer than Al but the way they dampen the shock is kind of wierd. In 5 years we will start seeing carbon really reach a level where it can out pace metals. It's the perfect material for building a bike, it's just a matter of mastering it. They can totally control it in every way, they can make things that bend in one direction but not others, they can control how it dampens and responds. They have also historically had custom processes for building it and as other figure it out how to do it well and it becomes more open knowledge we'll see more people experimenting with it.
For the time being, I think the future of high end racing bikes might start to switch to Ti as they figure out how to put carbon rears in and really master it. Even shaped Ti doesn't quite have the stiffness/weight ratio that a good Al frame has and you can get the Al much cheaper. As for weekending and touring, I think steel is still a very strong road bike contender and it's going to be a matter of making to Ti frames cheaper. Don't get me wrong, the litespeeds are awesome rides, they just cost a ton and they are doing amazing things with steels.
The problem with using titanium in applications such as jewelry or heaven forbid structures is its underlying crystal structure. Its very hard but not ductile, consequently when it breaks, it breaks in what my professor would describe as one big scary KA-BOOM. Not such a problem in jewelry, though if it did break it would be near impossible to repair, and the fragments would be sharp.
Bike construction depends mainly on design and geomotry, rather than material.
Alu, CroMo steel, Ti, Carbon fiber...any can be made great, or any can be made a noodle.
I buy titanium plate for use in jewelry production, it's not expensive. My rings start out as a hole drilled in a plate, so the thickness of the plate is the maximum width of the ring. a 1/4" thick 1-1/4" X 1-1/4" piece of titanium is somewhere between $10 and $20 depending on the grade...
From swordforum.com:
* Titantium - Most seem to think that the miracle metal would usually be "titanium" for swords. In actual fact, titanium is only a little better (and more expensive) than aluminum. (Both are usually in alloyed form, hence if a bar of titanium is purchased, it is usually a titanium alloy, similar to commercial aluminum being in alloyed form.) Both have a higher strength-to-weight ratio than steel. However, in the form of swords, titanium-alloy has not reached the hardness of steel in order to be of any effective use as a real sword. The best application in swords would be a thick-edged stage prop - however, aluminum will do just as well with negligible difference in performance and a tremendous savings in price.
I'll take high-carbon differentially hardened dendritic steel in my weapons baby! Sure you have to oil it, but at least as weaponry goes it is primo