The Magic of Titanium

Strange then that the more usual name for titanium dioxide is also titania, and like its namesake in the play it too has a rather mystical side to its nature as we shall see. There are abundant ores that could supply us with titanium - if we could find an easy way to free its spirit. We can obtain the metal but this is very difficult to do. 

In the 1950s, surgeons discovered that titanium metal was not rejected by the body and so was ideal for mending broken bones. It has been used in operations for hip and knee replacements, inserting cranial plates for skull fractures, and even for attaching teeth, some of 

59) The most abundant elements are oxygen and silicon, after which come the metals aluminium, iron, calcium, sodium, magnesium, potassium and titanium. 

60) Prince Charles had his broken elbow repaired with a titanium 

142 Better Living (III) Minor Metals for Major Advances 

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The magic of titanium results from its combination of toughness, stretchability, and resilience. A... 

The magic of titanium results from its combination of toughness, stretchability, and resilience. A bicycle that is built stiff to resist pedaling loads usually responds by giving a harsh, uncomfortable ride. A titanium bike is very stiff against high pedaling torques, but it seems to transmit much less road shock than bikes made of competitive materials. 

Figure 16. Mass distribution of TimCj clusters generated from the reactions of titanium with CH4. Note the "super magic" peak corresponding to TisCu. Taken with permission from ref. 92.

But even the magic of superconductors has its limits. Magnet designs involve relatively sharp bends in the conductor, a requirement which has led to difficulties with such materials as niobium-tin, a great superconductor but brittle compared to niobium-titanium. Cooling the conventional superconductors to extremely low temperatures is also a problem. And there is the propensity of the superconductors to lose their superconductivity—to go normal— in the presence of strong magnetic fields. 

The reaction sequence is summarized below using isobucane as the hydrocarbon. The crucial and nearly incredible part of the process is in two parts itself but only shows as one. It is the second equation where the oxygen molecule transfers to the propylene molecule and the ring closes to form the epoxide. (Thats why they call it epoxidation). The magic that causes all that to happen is in the metal catalysts, molybdenum naphthenate or the soluble salts of titanium, vanadium, or tungsten. This molecular fancy-dance is but one of nniany examples in chemistry where catalysts can cause atoms to slide around molecules in unlikely ways. 

Another magical titanium material is the alloy nitinol, which can remember a previous shape and return to it. Nitinol consists of 55% nickel and 45% titanium, a combination which corresponds to one atom of nickel for each atom of titanium. This alloy was developed in the US in the 1960s at the Nickel Titanium Naval Ordnance Laboratory which gave rise to the name Ni-Ti-NOL. This alloy is best known as spectacle frames which can be twisted in a way that would be permanently deformed were they to be made of any other metal but, because they are made of nitinol, they will jump back to their original shape when the pressure is removed. 

Of all these materials, titanium gives the bicycle that fanatics seem to love the most (Fig. 19.4). After their first ride on a bicycle with a titanium frame, most experienced cyclists find themselves shaking their heads and searching hard for the right words to describe the experience. Typically, the word magic is used a great deal in the ensuing description. 

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