Microstructure and evolution of iridium coating on the C/C composites ablated by oxyacetylene torch

Dense and adhesive iridium coating was obtained on the carbon/carbon composites by double glow plasma. The coating was ablated by an oxyacetylene torch to determine the stability of the coating at 2000 °C. Although some pores and the rumpling appeared on the surface after oxyacetylene flame, the integrality and adhesion of the coating kept up. The rumpling could be attributed to plastic deformation of iridium coating which resulted from expansion or contraction mismatch of the coating and the substrate. The ablation results indicated that iridium coating by double glow plasma could afford the high temperature up to 2000 °C and protect the carbon/carbon composites from quick oxidizing.