Titanium in a single step
6 Nov 2003
Researchers from QinetiQ believe that a new process for refining titanium could reduce the price of the metal, and open up new areas for its use.
Titanium still has the image of a space-age material - strong, lightweight, and incredibly expensive. But researchers from QinetiQ believe that a new process for refining titanium could reduce the price of the metal, and open up new areas for its use.
‘There is a huge potential market for titanium products, from components used in aircraft and automobiles to high specification consumer goods, such as sporting equipment and spectacle frames,’ says Stuart Wright, general manager of QinetiQ’s titanium powders business.
But the cost of the metal, which is a direct result of the refining process, can be prohibitive. Like most metals, titanium ore contains the metal oxide. To extract the pure element, the ore must be heated in batches with carbon and chlorine to produce hazardous titanium tetrachloride, which is then reacted with magnesium.
QinetiQ, formerly part of the UK government defence agency DERA, has been working on a new electrochemical process for producing titanium for five years.
Developed by Derek Fray, Tom Harding and George Zhang Cheng at Cambridge University in 1993 and now known as the FFC Cambridge process, the technique works by reducing a cathode made out of titanium dioxide, or a mixture of oxides including TiO2, directly to pure titanium or a titanium alloy.
The metals are produced in the form of powders or a metal sponge, which can be melted or compressed to form an ingot. ‘We are even developing the ability to directly manufacture near net shape products, thereby avoiding add-on costs produced by specific tooling or patterning requirements,’ says Wright.
The new process is ready to go to production scale, and Wright expects to start selling high-quality powders of pure titanium and alloys from next year. Orthopaedic patients are likely to be among the first to benefit.
‘Titanium is an ideal material for use as implants, and the development of rapid manufacturing technologies will enable complex parts and prototypes to be quickly and cost-effectively manufactured,’ Wright says.
