# Most heat resistant material? **URL:** \ **Category:** Factual Questions\ **Created:** [March 16, 2006, 5:23pm UTC](https://boards.straightdope.com/t/most-heat-resistant-material/348621 "2006-03-16T17:23:25Z")\ **Posts on this page:** 11\ **Page:** 2
**Author:** ![Sicks\_Ate](https://avatars.discourse-cdn.com/v4/letter/s/258eb7/32.png) [@Sicks\_Ate](https://boards.straightdope.com/u/Sicks_Ate)\ **Post date:** [January 16, 2014, 1:57am UTC](https://boards.straightdope.com/t/most-heat-resistant-material/348621/21 "2014-01-16T01:57:05Z")
I used to work in a foundry, and every once in a while they’d have to overhaul a furnace. The refractive material was put on wet, kind of plastered on. It went on about a foot thick that I can remember. I never got curious enough to ask what it was made out of…any ideas? ---
**Author:** ![Napier](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@Napier](https://boards.straightdope.com/u/Napier)\ **Post date:** [January 17, 2014, 3:50am UTC](https://boards.straightdope.com/t/most-heat-resistant-material/348621/22 "2014-01-17T03:50:09Z")
A trillion degrees, for degenerate neutrons in a neutron star. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [January 17, 2014, 3:52am UTC](https://boards.straightdope.com/t/most-heat-resistant-material/348621/23 "2014-01-17T03:52:39Z")
Nah, neutron stars don’t cut it, since the OP is looking for a solid. Neutron stars are superfluid. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [January 17, 2014, 4:04am UTC](https://boards.straightdope.com/t/most-heat-resistant-material/348621/24 "2014-01-17T04:04:34Z")
> [@Sicks\_Ate](#): > > I used to work in a foundry, and every once in a while they’d have to overhaul a furnace. > > The refractive material was put on wet, kind of plastered on. It went on about a foot thick that I can remember. > > I never got curious enough to ask what it was made out of…any ideas? Aluminum and Calcium oxides are the primary ingredients in refractory materials. There may be other materials which are more heat resistant, but they wouldn’t be as inexpensive, and none of these materials last all that long at very high temperatures and have to be replaced often. ---
**Author:** ![Lumpy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lumpy/32/446_2.png) [@Lumpy](https://boards.straightdope.com/u/Lumpy)\ **Post date:** [January 17, 2014, 3:15pm UTC](https://boards.straightdope.com/t/most-heat-resistant-material/348621/25 "2014-01-17T15:15:48Z")
Ah, some random searching and I found Wikipedia’s article on Thorium Dioxide, which claims ThO2 has the highest melting point of any oxide- 3390C. Higher than most elements and all but a handful of compounds (Tantalum carbide, etc.) ---
**Author:** ![Napier](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@Napier](https://boards.straightdope.com/u/Napier)\ **Post date:** [January 19, 2014, 10:42pm UTC](https://boards.straightdope.com/t/most-heat-resistant-material/348621/26 "2014-01-19T22:42:50Z")
> [@Chronos](#): > > Nah, neutron stars don’t cut it, since the OP is looking for a solid. Neutron stars are superfluid. “The surface of the neutron star is made of iron. In the presence of a strong magnetic field the atoms of iron polymerize. The polymers pack to form a lattice with density about ten thousand times that of terrestrial iron and strength a million times that of steel.” Neutron star surfaces, then. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [January 20, 2014, 1:49am UTC](https://boards.straightdope.com/t/most-heat-resistant-material/348621/27 "2014-01-20T01:49:10Z")
OK, that’ll work, though the surface isn’t subject to nearly the same heat that the interior is. ---
**Author:** ![j\_sum1](https://avatars.discourse-cdn.com/v4/letter/j/8baadc/32.png) [@j\_sum1](https://boards.straightdope.com/u/j_sum1)\ **Post date:** [January 20, 2014, 3:00am UTC](https://boards.straightdope.com/t/most-heat-resistant-material/348621/28 "2014-01-20T03:00:14Z")
> [@Napier](#): > > “The surface of the neutron star is made of iron. In the presence of a strong magnetic field the atoms of iron polymerize. The polymers pack to form a lattice with density about ten thousand times that of terrestrial iron and strength a million times that of steel.” > > Neutron star surfaces, then. Wooo!! You learn something new every day. > [@Chronos](#): > > OK, that’ll work, though the surface isn’t subject to nearly the same heat that the interior is. Not nearly the same temperature as the centre of a neutron star is surely a relative term. I bet that it is still pretty hot. Back to the polymerised iron. I am going to assume that we are talking Fe nucleii here and that they are stripped of electrons. Or maybe not if it is a magnetic field that causes the structure to exist. As a structural material (hypothetically), 10000 times the density and 1000000 times the strength sounds like a pretty good sort of a trade off. I have got to wonder what force holds the lattice together. It doesn’t sound like a typical chemical bond. And this is getting way hi-jacky. If there isn’t a short answer, maybe it’s worth starting a new thread. Colour me intrigued. ---
**Author:** ![Napier](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@Napier](https://boards.straightdope.com/u/Napier)\ **Post date:** [January 20, 2014, 3:21am UTC](https://boards.straightdope.com/t/most-heat-resistant-material/348621/29 "2014-01-20T03:21:17Z")
> [@Napier](#): > > “The surface of the neutron star is made of iron. In the presence of a strong magnetic field the atoms of iron polymerize. The polymers pack to form a lattice with density about ten thousand times that of terrestrial iron and strength a million times that of steel.” > > Neutron star surfaces, then. Cite?! Oh, wait, that was me. It’s from the Wikipedia article on “Neutron Star”. ---
**Author:** ![Lumpy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lumpy/32/446_2.png) [@Lumpy](https://boards.straightdope.com/u/Lumpy)\ **Post date:** [January 20, 2014, 2:41pm UTC](https://boards.straightdope.com/t/most-heat-resistant-material/348621/30 "2014-01-20T14:41:09Z")
Since such iron is held in that state by gravitational and magnetic pressure and isn’t stable otherwise, it’s not like anything could ever be made out of it. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [January 20, 2014, 3:17pm UTC](https://boards.straightdope.com/t/most-heat-resistant-material/348621/31 "2014-01-20T15:17:51Z")
The magnetic forces, while ludicrously strong by Earthly standards, still pale in comparison to the gravitational effects. And yes, even the surface of a neutron star is hotter than you’ll find in most Earthly contexts, certainly hotter than any terrestrial material can withstand. Amusingly, though, it’s also true to say that the temperature of a neutron star, even in the core, is “approximately zero”, since the thermal energies of the particles are far, far less than the Fermi energies, and thus insignificant. [Previous page](https://boards.straightdope.com/t/most-heat-resistant-material/348621.md?page=1)