Platinum Metals Review - Volume 9, Issue 3, 1965

Platinum, iridium, rhodium and palladium are among the few metals that may be examined by field ion microscopy, in which it is possible to magnify the image of a prepared surface so that individual atoms are revealed. This technique, by which such factors as plastic deformation, gas adsorption, fatigue, dislocation structure and the effects of impurities can be examined, may well lead to a better understanding of the valuable properties shown by the platinum metals in their catalytic, electrochemical and high temperature applications.

Most of those industrial processes involving the bulk handling of molten glass would be facilitated if the platinum surfaces employed were more resistant to wetting. No reliable information on this subject has hitherto been published, and some recent work in the Johnson Matthey Research Laboratories has demonstrated the complexity of the high temperature relationships encountered. The way in which glass reacts with pure platinum is described in the first part of this paper. Subsequent parts will show how the equilibrium contact angle increases gradually with increasing rhodium content and more rapidly with the addition of small quantities of gold. The resistance to wetting of certain of the rhodium-gold-platinum alloys will then be correlated with their microstructure and physical properties.