 Johnson Matthey, Hatton Garden, London. |
A History of Iridium
OVERCOMING THE DIFFICULTIES OF MELTING AND FABRICATION
Platinum Metals Review
Article Synopsis
The use in unmanned space craft of iridium to encapsulate the radioisotope thermoelectric generators, where temperatures of up to 2000°C have to be withstood over several years of operation, with possible impact velocities of 90 metres per second, has focused greater attention on the remarkable properties of this member of the platinum group of metals. But these same properties of very high melting point and great mechanical strength have been the cause of difficulties in its melting and fabrication over a long period of years. How these problems were tackled and eventually overcome is described in this article.