Preliminary study of iridium coating on carbon/carbon composites

Abstract

Iridium coating was deposited on as-received, polished and chemical vapour deposited (CVD) pyro carbon-coated carbon/carbon composite by d.c. sputtering. The as-received surface of the carbon/carbon composite was not fully covered by an iridium coating up to 12 μm thick, whereas better deposition and surface coverage with the iridium coating were obtained on the polished surface and CVD pyro carbon-coated carbon/carbon composite surface. After heat treatment at 2000 K for 1.2 ks, interconnected islands of iridium were formed on three surfaces of the carbon/carbon composite. Iridium neither reacted with nor dissolved the carbon/carbon composite, it had some penetration but did not react to form an interfacial compound, and the boundary between the iridium and carbon/carbon composite was distinct.