Titanium is a strange material, not least for the myths surrounding it. It is often described as being incredibly hard, or incredibly strong, when the truth is that it is neither. It can be impressively strong compared to its density, but it does not stand out in this respect. It has been very expensive, and to the man on the street it has the reputation of being out of reach. It is, however, no more expensive per unit mass than many grades of steel or aluminium. It is widely used in...