Sciencemadness Discussion Board

Need a heat resistant yet heat conductive material to coat steel sheet

RogueRose - 4-2-2016 at 13:15

I need to prevent the steel in a burn chamber from burning through and I know putting thicker gauge steel is an option at times, in this case, I need to go a different route of adding a protective layer of some type to the steel.

The steel is fairly thin gauge (think oil drum thickness). I'd like to coat it or build a layer of ???? to protect it from the oxidation of flames and any vapors from whatever is burning. In this case, I need something that is as conductive to heat as possible (transfer heat to steel sheeting) while being tough and resistant to whatever is being burned in the chamber. Ideal thickness applied would be about 1/2" thick (metal mesh can be applied to give support & structure) but could probably go a little thicker (say 1" max) if need be.

The reason I haven't just used something like furnace cement is because I have no idea how conductive to heat it is and I have been told that it can vary greatly from product to product. I am hoping that there may be something that can either be added to the cement or I can make my own refractory myself if it would give superior results in conductivity.

Temp requirements:
Fuel will be wood & whatever waste products are manufactured to burn in stoves these days (corn, pellets, chips, etc), propane torch, fuel oil possibly. There will most likely be a blower adding air if needed for some fuels but most will probably be normal atmospheric conditions. I don't see this fire reaching above 1800F when pushed to it's max on a VERY rare occasion. Normal operating temps probably 700-1200F.

While I know this isn't chemistry as far as putting things in beakers and it isn't exactly metallurgy either. As cements and refractories are basically chemical mixtures, I thought it would be acceptable to ask in this forum, if I am mistaken I apologize. I figured that someone may know a heat resistant conductive material which may help in this situation. Thanks for consideration and any help rendered!

jokull - 4-2-2016 at 14:13

Hi RogueRose,

may you explain the problem you are trying to solve?
As I read your post it seems that the concern is about aesthetics of the steel sheet. If so, you may use a second steel sheet as lining.

Refractories are used when you want mechanical stability under high temperature conditions (>1000ºF) but they are not commonly intended to conduct heat.


RogueRose - 4-2-2016 at 15:52

Quote: Originally posted by jokull  
Hi RogueRose,

may you explain the problem you are trying to solve?
As I read your post it seems that the concern is about aesthetics of the steel sheet. If so, you may use a second steel sheet as lining.

Refractories are used when you want mechanical stability under high temperature conditions (>1000ºF) but they are not commonly intended to conduct heat.




Sure, the gauge of the steel is a little thin for long term use and corrosion is a major issue as a small breach would lead to failure (leakage of fluid from outside into burn chamber). The refractory is simply to give an extra layer of protection to increase longevity. I guess an extra layer of steel would be the best choice as long as I can get it to contour to the chamber as best as possible.

Aesthetics are not an issue at all. I am worried about the heat of the combustion erroding the wall of the burn chamber - so I thought adding a layer of (refractory whatever) would give added protection.

I may be under a misconception that fire burns through steel eventually. I had a steel drum as a burn barrel and in about a year or so, it had turned to a pile of rust (although there were holed in the bottom, but most of the entire barrel had rusted).

The burn chamber will have some kind of liquid on the outside of it be it mineral oil, vege oil of some type or water (it will have a high circulation rate to keep below any ignition or boiling points).

So, a hole, especially if water is used, will be exacerbated by rust, and any hole will leak constantly. This is why I wanted a refractory (conductive) of some type to protect it.

If there is some conductive cement, that would still be ideal, but I'm thinking steel sheet cut in 1/2 to 1/3 circumferences and placed in pieces may work well too.