Ask the Expert Question-and-Answer Archive

by Ron Joseph

February, 2004

Protecting Substrates for Ultra-High Temperature

Q. I am trying to locate a coating that can handle an impulse temperature rise of 2000C (this temperature is only held for 1 second) and provide protected on the other side of the substrate. Have any recommendations?

A. Have you thought of ablative coatings? These are epoxy coatings that are filled with asbestos (at least I think that they contain asbestos) and are used on launch pads at Kennedy Space Center and other missile launching sites. Here too, extremeley high temperature resistance is required for a very short time only ... during the launch. These coatings are not easy to apply and require some experience, Also, they are not decorative, but strictly functional.

Depending on the application you might also consider intumescent coatings. These are used to protect substrates from fires for one hour or more. Intumescent coatings expand upon exposure to the high temperature and form a carbonaceous foam. Depending on what you intend to coat it is possible that you might need to replace the coating after the exposure. If the expanded coating is not disturbed after the first exposure, you might not need to replace it, but if it can get damaged, or if you intend to subject the substrate to this high temperature frequently, then this might not be your best choice.

Please be more specific about your needs, and when you make a decision please let me know, for my own interest.