Material....

There are very few materials that are solids at that temperature. Tungsten (atomic symbol W) is the only thing that comes to mind, but I don't know what pressures it can withstand.

I would suggest calling up a company that manufactures ovens that will reach that temperature and seeing what they suggest.

I would be very interested in finding out what you are trying to do.

Thank u very much for ur kind information indeed..... Already we were thinking about Tungsten but we are not happy with it since there is no materials combined with tungsten..

I got one more information from my collegue that Ceramic combined materails can withstand somewhat max temperature but we are not sure about it.. If u know any details i this u can give it to me...

K i ll try to contact any oven manufacturers to get this detail and let u know if i get any information on that.

here is a page that has some useful info for you to consider, with several directions that you could take it:

http://en.wikipedia.org/wiki/Thorium_dioxide

You might want to check out carbon fiber materials with ceramic coating.

Good Luck!

Typically in mechanical design pressure vessels have some temperature gradient that accompanies thepressure gradient to an outside set of conditions. Is that the case in your application? If so then an outer member at a lower temperature could provide the compressive load needed to prevent the inner high temperature member from experiencing stresses that will take it to failure.

If that is not the case then some analysis and experimentation with rates of temperature rise may lead you to a refractory alloy or material that will work without sufferinfg damage from thermal shock or differential thermal expansion.

Another important consideration is the physical size of your hardware. Extreme conditions at a size range of millimeters or fractions thereof are much easier to deal with in the real world of practical material applications than are meter sized projects.

Ed Weldon

Nothing will do what you ask - as you asked the question.

What is the use then as others have pointed out maybe a work around can be done.

Only ceramic and refractory materials only can withstand the temperature of 3000⁰ C and above.

Further, the designer who has designed his requirement, would have selected the materials and mentioned in his design/drawing and how come you are searching for it at the time of fabrication.

Please check up with your designer also. May be it could a SS or an alloy material which may require ceramic coating /plasma spray to withstand the end temperature.

Sridhar.

"Try.... Try.... Try.... Definitely you will get something..."

Yes; I will try to motivate Rajiv_Vayu to communicate with those of us seeking to be of assistance....... Here is a possible course of action:

Note, while the purpose of this tubular member is not yet established in this discussion I will refer to a likely use, that being a reactor of some sort.

Pick a suitable ceramic as the primary reactor material. This must be made into a tubular shape. This can be accomplished either by forming an initial cylinder and diamond core drilling it to final size or by forming the ceramic around a cylindrical removable core. Said core may be contrived to be removable either by mechanical means or by chemical action (perhaps a soluble salt, traces of which must be compatible with the final use of the reactor.) Final finishing of the ID can be accomplished by diamond grinding using an arbor like tool mounting specially built for this project.

Now having produced the reactor lining tube it is necessary to provide the structure that will support the high internal pressure conditions. Here, in the absence of contrary information it is reasonable to assume that this outer support structure, which should be a tube of uniform thickness to prevent localized stress risers, will operate at lower temperatures which will be a function of the heat transfer characteristics of the assembly when in use.

The formation of the outer tube should be done in a manner that places it in substantial tension. The material properties of the outer tube as well as it's thickness should be determined by its ability to retain properties and therefore it's ability to hold the inner ceramic tube in a state of compression at the calculated temperature at which it's inner surface operates.

A likely selection of metal for the outer tube will be one which can be formed by casting around the inner tube, which must be carefully preheated to the molten metal temperature prior to pouring the casting to prevent thermal shock. As the casting cools (perhaps taking days to reach room temperature) the metal with it's higher coefficient of thermal expansion slowly prestresses the ceramic inner tube into a state of compression, thereby enabling it to withstand the high operating pressure during future operational cycles.

Some additional design effort using the same line of thinking as just described would be necessary for the end closures of the reactor. Fortunately this can be accomplished by outer structures that need not be at great elevated temperatures and can be removed from the requirement to operate under controlled conditions of heat transfer.

I should note here that the necessary assistance of a competent metallurgist to determine accurately the high temperature properties of the outer metal tube. Generally published data on material properties may not be adequate to reach a successful development conclusion.

Ed Weldon

Until we understand the use of the equipment all is for nothing. A combustion chamber at these temps is a tricky thing and I expect that is what they want.

Kryptonite! Red or Green, your preference.

Ceramic ceramic and ceramic will do this.

Ceramics needs to based on Hafmium oxide dopped tunston oxide pipe and will stand 4000 oC

And the pressure? No it will not.

Will Ceramic withstand the pressure of 400 bar..

Yes

If this is glass ceramic it will

Give an example of this magic stuff - ceramic that holds 400 barg.

3000 degrees C is a bit on the hot side - above the melting point of glass - silica melts at 2300 deg C.

You can have 3000 deg C inside a chamber but it is tricky.

Make aluminum titanate glass

Make slurry

Cast in pipe

Heat treat to crystallize using hafmium oxide as dopant

Take this to 3000+ oC and will be okay

Aluminum titanate is formed at the works at high temps but less than 3000 deg C. It is not made in a slurry form and cast.

Mechanical strength, typically, is low.

Quote: Aluminum Titanate ceramic materials ceramics are used for manufacturing crucibles, launders, nozzles, riser tubes, pouring spouts and thermocouples for non-ferrous metallurgy, portliner and cylinder linerrs in automotive engines, master moulds in the glass industry, spacing rings of catalytic converters.

I have used the material at the outlet of an iron ore reduction furnace where the good wear characteristics were important.

If you dop this with HAfmium oxide its use temperature goes to 3000 oC

You are correct for pure aluminum titanate every thing you said. If you see the email there is dopant which is Hafnium oxide to increase its usability temperature. I wish I can spell out actual percent of this oxide but we can discuss this over separately

That temperature will have to be controlled with a refractory lining, a hot face of an insulating brick and a outer layer of a hard brick, the metal shell would then have to control the pressure.

The thickness of the insulating and hard brick would have to be thick enough to control the cold-face temperature.

You should consult a refectory suppler, there might be a Gunnite refractory that might meet your requirements.

You need to consult with a refractory expert. There are insulating brick that backed with a hard refractory brick that should handle the temperature and help withstand the pressure. You will have to have a metal shell that will hold the pressure and survive the cold-face temperature.

There may be a Gunnite type (spray on) refractory that will meet your the temperature and pressure requirements, again consult with qualified refractory expert.

Actually its a Pressure Vessel Pipe closed on both ends and kept vertically by supports.. Pressure will be applied from the bottom..-- Is the requirement of the Guest.

Then it will not be possible to overlay with ceramic bricks inside the pipe.

We can only spray on the inside wall and coat it.

A high pressure combustion chamber?