Platinum Metals Review - Volume 29, Issue 1, 1985

The sophistication possible with modern electronic and microelectronic devices depends ultimately on the materials from which they are made. The platinum metals have assumed a vital role in electronics at every stage in its evolution. They are found in both thin and thick film devices which together constitute the backbone of electronic manufacturing technology and overall this area represents one of their main applications in terms of metal consumption.

The technology for extracting pure hydrogen from hydrogen-rich gas mixtures by diffusion is now well established. The success of the process and the demand for the product has led to the formation of Johnson Matthey Equipment, a company devoted to the supply of equipment based upon the properties of the platinum group metals, principally hydrogen purification and generation equipment.

One of the major maintenance problems for gas turbine engine operators is the degradation of high pressure turbine blades and vanes. The Australian Department of Defence was experiencing unacceptably high rejection rates of these components in one of its high performance engines as a result of severe hot corrosion attack. Accordingly a programme was initiated to find a more durable coating than the conventional aluminide coating supplied for the first-stage blades by the engine manufacturer. The coating chosen for the trial was a platinum-modified aluminide coating. Metallographic examination of both coating systems after 750 hours of service in an operational aircraft clearly established the superiority of the platinum-modified coating. This coating has now been adopted by the Australian Defence Force as the specified coating for first-stage blades in this engine.