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Titanium As Cheap As Aluminum?
ThesQuid writes: "I caught this article in The Economist the other week. If practical, the electrolytic process described could make the production of titanium as cheap as aluminum. Ridiculous? Just remember, aluminum used to be refined by a process somewhat similar to how titanium is refined nowadays, and when a practical electrolytic refining process was discovered the price of it went from more precious than gold to something, well, as cheap as aluminum is nowadays."
In Genius , the Richard Feynman biography, there was an anecdote where the scientists working on the nuclear bomb at Los Alamos discovered they could requesition *anything* from the army. After asking for and recieving a 12 inch diameter solid sphere of gold (later cut in half and used as a door stop) they asked for a kilogram of osmium, only to be turned down when it was discovered that that significantly more than existed in pure form in the entire world at that time.
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I'm a machinist, and as an Expert In The Field, yeah, it would be neat to see a titanium beer can, but....
Titanium is a *bitch* to work with. It does *not* want to be worked. It doesn't like to be turned, milled, or ground, and if you're using a surface grinder and oil as a coolant, keep a fire extinguisher handy.
Or just shut off the oil.
I don't even want to imagine what it's like to weld.
Anyway, I digress...
Yeah, it'd be cool to see titanium as cheap as aluminum. It could be useful where aluminum cannot take the place of steel. It still won't make aluminum any less useful. Aluminum is *much* easier to work with (6061 alloy, anyone?), and therefore, less expensive for a finished product. You'll still see aluminum beer cans and aluminum engine blocks in the future.
Titanium is as strong as steel, but 45% lighter. It is 60% heavier than aluminum, but twice as strong. Not surprisingly, it is often used in aircraft and missle hulls, as well as lacrosse sticks and mountian bike frames. It's used in that rainbow-hued metallic jewlery available at the mall. Because it's not corroded by salt water, it's used in desalination plants, propellers and other marine applications (including lures). Titanium is used to make "Shape memory alloys", notably nitinol (nickel-titanium). You can use nitinol wire to make walking robots, with the nitinol used as the musculature. It it used in pigments and is what makes white toothpaste white (TiO2). In fact, this is its major use. Plus, it's shiny. :)
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Napster-to-go says "Fill and refill your compatible MP3 player", which is a lie. It's not MP3. It's WMA with DRM.
Well if you want to get technical about it Aluminum makes up 8.2% of the crust. Titanium makes up .56% of the crust. On top of this all Aluminum is mined from highly leached clay deposits near the surface. These deposits are formed in areas with a tropical climate and were only formed in the last 60 Million years. The Soviets tried getting Aluminium out of igneous rocks earlier this century. They even couldn't make Aluminum in an economical manner.
At any rate Titanium is obtained from rutile or Ilmenite that are from ocean beach sands or titianium bearing igneous rocks. In the late 80's and early 90's the US produced 25,000 metric tons per year of Titanium metal. The other major use of Titanium is white piment for paints and for the same period, 1 million metric tons of Titianium pigment was produced per year. By contrast the US used 6 million metric tons of Aluminum in the mid 1990s. At any rate due to the rarity of Titanium deposits I doubt that Titanium will ever be as cheap as Aluminum. For that matter Titanium is a much harder metal than Aluminum and wears out tools that manufacture Titanium much faster. It is possible though that Titanium will be used in place of Aluminum in many cases. Don't count on Titanium replacing Aluminium cans though.
Impersonating Tycho from Penny Arcade since before there was a PA.
Here are a few more facts about Titanium:
Titanium isn't a superstrong superlight alloy- On the periodic table, as you move up and to the left, the solid elements have an increasing strength-to-weight ratio. This means that Beryllium is the lightest/strongest metal for practical use. Aluminum even has a higher tensile strength-to-weight ratio than titanium. Why isn't aluminum considered a ubermetal, similar to titanium? I think it is. One problem with aluminum is that it fatigues when it flexes. This is why aluminum bicycles have thick thin-walled tubes, so they can't flex. When properly designed, aluminum will provide a better strength-to-weight ratio than titanium.
Titanium will always be harder to work with than aluminum- Aluminum is lightweight and easy to work with. The industry has over 50 years of experience working with aluminum, whereas they have 30 years of good experience with titanium. Commercial products (golf clubs, bicycles) didn't start using titanium until the '80s and the decline of the Cold War, when the military-fed companies had to start selling to the civilian industry. Even after titanium knowledge gets closer to what we know about aluminum, we will continue to push aluminum, since it is cheaper and softer (i.e. cheaper to work with).
Titanium does have great properties- Did you ever wonder why many titanium bicycles don't have any paint? There's no paint because they don't need any, titanium is one of the least reactive metals there is (ironically, this is what makes it hard to process, too). So, where other metals have to be painted to reacted to prevent corrosion, titanium is fine as it is. This property also makes titanium nice for biological applications (bones, valves, etc.).
Another nice property of titanium is its resilience. Titanium has a relatively large linear elastic strain region, i.e. it's very springy. This is what makes titanium great for bicycle seat rails, but not neccessarily bicycle frames (unless you like the wet-noodle feeling on a bike). Before you flame me, realize that good design prevents this.
Titanium may become cheaper than steel- I wish someone else would have pointed this out. Now that they can process titanium in one step, it may have a chance to compete with steel. Since we have been forming steel since the middle ages, it has a long way to go, but due to its strength-to-weight properties, corrosion resistance, and resiliance it could easily surpase Steel as the cheap standard metal. Perhaps the lack of painting on titanium can make up for its higher temperature (higher temp->more energy->more $$$) of processing. Since it would have a higher working temperature I could easily see it being used in engines and buildings. Ti's resilience may create for very Earthquake proof/fire proof buildings. If you talk to someone who works with Ti, they will say that it is too funky to machine and work with, it's resilience fights back against the machinist. I think that the machinists need to get used to the metal and that is all.
If you read all the way to the end of this, now you'll see the good part- Titanium has many applications in the area of nanotechnology. TiNi has shape-memory properties which means that you can do cool stuff with it. For example, I've stretched TiNi Super-elastic wire. Basically, it was a wire that stretched similar to a rubber band. Also, by alternating thin layers of TiNi on the surfaces of other metals you can create various thermal strains and stresses due to thermal expansion anisotropy. A practical application of this are new forceps used in brain surgery. A human hair is ~100-300 microns in diameter, while these forceps are ~0.6-1 microns in diameter. Brain surgens use these to hold brain neurons while performing surgery.
I think that is amazing. Just in case you were wondering what a grammar nazi knows about Materials Science, don't.
Keeping