Iridium coating layer for carbon material anti oxidation and its preparation method

Abstract

This invention relates to a type of carbon material iridium smear layer used for antioxygen. The feature is it has two iridium smear layer: one permeates under carbon material; one deposit on the surface. The depth of infiltrated layer is 10-50um, surface layer is 50-300um. Iridium and carbon material has combined, and the ingredient forms gradient transition from infiltrated layer to surface layer and has no catastrophe of ingredient and mechanical property. The preparation of this smear layer includes follow steps: use iridium board and carbon material as cathode, vacuum chamber shell as joint using anode in the vacuum glow discharge installation; draw vacuum to ultimate vacuum, post in argon gas, light aura, and then alloy elementary particle of source electrode iridium target is sputtered and deposit on the surface of carbon material; the last step is high temperature diffusion.

Description

technical field [0001] The invention relates to an iridium coating and a preparation method thereof, in particular to an iridium coating for oxidation resistance of carbon materials and a preparation method thereof. Background technique [0002] Carbon materials include graphite single substance materials and carbon / carbon composite materials, which have low density, high specific strength, thermal shock resistance, creep resistance, and strength increases with temperature between 1000 ° C and 2200 ° C. They have been used in strategic missile warheads , spacecraft return capsule, space shuttle wing leading edge and other aerospace vehicles have been applied. However, since carbon materials react with an oxidizing atmosphere above 400°C to generate carbon monoxide or carbon dioxide volatilization, solving the problem of oxidation resistance of carbon materials is a bottleneck for the wide application of carbon materials. At present, a variety of ceramic anti-oxidation coati...

AI Technical Summary

Problems solved by technology

The advantage of this method is that the iridium coating is uniform, and a dense iridium coating can be obtained by multiple chemical vapor deposition; the disadvantage of this method is that the cost is high, the price of iridium triacetylacetonate is as high as 1100 yuan / gram, and the iridium coating is not wet with carbon. Wet, high temperature treatment produces a lot of cracking, low anti-oxidation and anti-scourability

[0007] The above-mentioned research status shows that although iridium coating is considered to be a very ideal carbon material anti-oxidation coating, there is no method to prepare high-quality iridium coating, which is the problem to be solved by the present invention