New High Temperature Material

[JasonAW3]

A lot of you probably already know about this,  But I was wondering if anyone could think of any uses for a High Temperature material that won't melt at 4400K or about 7,460 degrees Fahrenheit.

http://gizmodo.com/this-material-wouldnt-melt-even-at-the-center-of-the-e-1720668975

Original article at;

https://news.brown.edu/articles/2015/07/melting

     I was thinking of the obvious, thermal protection systems and rocket engine linings, but not knowing how fragile this material would be, I figured I'd see if someone else could come up with better uses.

[Lee Jay]

Turbine blades (jet and rocket).

[john smith 19]

It's roughly Hafnium Carbide Nitride.


Note that at this point no one has actually made this compound.

Hafnium has an S.G of about 13.3, so it's about 2x that of Nickel. It's Carbon and Nitrogen so likely a ceramic in terms of brittleness.

Thermal Barrier Coatings are known used in the aircraft engine business to raise turbine operating temperatures. 

The two issues are how it handles exposure to Oxygen and wheather the density difference is significant enough that it could cause trouble with adhesion to blades.

The easiest option is for use as a combustion chamber or gas generator lining, since they normally run fuel rich, then as a next generation TPS if its oxidation resistance is up to the job (RCC's use temperature is amazing in a vacuum.  In air it's all about the quality of the oxidation resistance coating). That leaves the use of TBC on turbine blades. However AFAIK they are not used on rocket engine turbines to begin with I'm not sure how much use a better coating would be, although probably quite a lot on regular turbines.

[Andy Smith]

Nuclear thermal rocket containment chamber?

High melting point and potentially high levels of neutron absorption would seem to make this worth looking at?

[john smith 19]

Nuclear thermal rocket containment chamber?

High melting point and potentially high levels of neutron absorption would seem to make this worth looking at?

Yes that would be a pretty good choice. IIRC NERVA and it's ilk were looking at about a 2000c chamber and this would let them either run hotter or give lots of temperature margin. Might give an NTR with an Isp of 1000secs.

More exotically you could go with the gaseous "nuclear light bulb" concept. Unfortunately this material is likely to be opaque. that said it could run so hot it would re-radiate from its back surface.

That however is very  speculative. I'd settle for a low maintenance TPS (which 25 years after the X33 and 35 years after the Shuttle still  does not exist  ).

[Tetrakis]

Periodically, a thread is started which talks about big claims being made by computational chemists. Not to be a wet blanket, but there appears to be no experimental evidence for such a substance. It may not actually be possible to make it at all, even if it does have the predicted properties. I will also note that computational methods involving organometallic bonds such as those in HfC are far from what I would call mature; extensive calibration is required, so their validity is only expected within a small radius of chemical change from known species. Further complicating matters is that periodic calculations of melting point in three dimensional lattices is relatively unreliable.

My opinion on these sorts of findings: great. Synthesize the species, test it, then publish the rationally designed material. Simulated results often fail to give accurate predictions.

[JasonAW3]

Periodically, a thread is started which talks about big claims being made by computational chemists. Not to be a wet blanket, but there appears to be no experimental evidence for such a substance. It may not actually be possible to make it at all, even if it does have the predicted properties. I will also note that computational methods involving organometallic bonds such as those in HfC are far from what I would call mature; extensive calibration is required, so their validity is only expected within a small radius of chemical change from known species. Further complicating matters is that periodic calculations of melting point in three dimensional lattices is relatively unreliable.

My opinion on these sorts of findings: great. Synthesize the species, test it, then publish the rationally designed material. Simulated results often fail to give accurate predictions.

I think that that is pretty much the same thing that was said about the 77 Degree C superconductor, but it exists now and islikely to make for some very interesting changes in teh next 20 years.

[Tetrakis]

Perovskite superconductors were an accidental discovery.

Edit: I read Kelvin when you wrote Celsius. Citation needed, bub.

[Moe Grills]

A lot of you probably already know about this,  But I was wondering if anyone could think of any uses for a High Temperature material that won't melt at 4400K or about 7,460 degrees Fahrenheit.

http://gizmodo.com/this-material-wouldnt-melt-even-at-the-center-of-the-e-1720668975

Original article at;

https://news.brown.edu/articles/2015/07/melting

     I was thinking of the obvious, thermal protaction systems and rocket engine linings, but not knowing how fragile this material would be, I figured I'd see if someone else could come up with better uses.

Thorium-oxide's melting temperature falls short of the temperature you gave, but it's not far off. Thorium-oxide is an excellent refractory material. It would make excellent fuel-rod material for a nuclear thermal-rocket motor.

[JasonAW3]

Perovskite superconductors were an accidental discovery.

Edit: I read Kelvin when you wrote Celsius. Citation needed, bub.

You know what? You're right!  I did screw up.  it was supposed to be 140 Degrees C or about 149 F!

http://www.superconductors.org/141C136C.htm

Thank you for catching that!

[Tetrakis]

Perovskite superconductors were an accidental discovery.

Edit: I read Kelvin when you wrote Celsius. Citation needed, bub.

You know what? You're right!  I did screw up.  it was supposed to be 140 Degrees C or about 149 F!

http://www.superconductors.org/141C136C.htm

Thank you for catching that!

I've spent enough time tilting at pseudoscientific windmills over on the EMDrive thread, but that hardly counts as a credible source for a claim of "hot" superconductivity. If this board is to maintain respectability there need to be standards.

Statements on the linked page such as this:

"While the scientific community continues to pretend that room-temperature superconductivity has not yet been achieved, Superconductors.ORG herein reports the discovery of room temperature superconductors number 25 and 26 - further advancing the world record for high Tc."

firmly place that author in tin-hat territory.

Back on topic, quantum chemical methods do not have the strong predictive power as, say, CFD and other classical physics simulations. This is based on my own experience with molecular quantum chemistry and my discussions with people working in solid-state theoretical chemistry. I would suggest taking these theory papers with a huge grain of salt until they are backed up with experiments.

[john smith 19]

Thorium-oxide's melting temperature falls short of the temperature you gave, but it's not far off. Thorium-oxide is an excellent refractory material. It would make excellent fuel-rod material for a nuclear thermal-rocket motor.

Thorium  Oxide is an excellent refractory, and a lot of work was done on it up until maybe the mid 70's. Unfortunately you have the issue that it's radioactive.

Perhaps if Thorium reactors become a reality there will be a supply of depleted Thorium available for such purposes.

[Damon Hill]

Thorium-oxide's melting temperature falls short of the temperature you gave, but it's not far off. Thorium-oxide is an excellent refractory material. It would make excellent fuel-rod material for a nuclear thermal-rocket motor.

Thorium  Oxide is an excellent refractory, and a lot of work was done on it up until maybe the mid 70's. Unfortunately you have the issue that it's radioactive.

Perhaps if Thorium reactors become a reality there will be a supply of depleted Thorium available for such purposes.

There is no such thing as "depleted" thorium, it's virtually all one isotope, and that's the least radioactive one with a half-life in the multiple billions of years.  Naturally occurring 232Thorium itself is not fissile; it must be converted to 233Uranium to fission.

[A_M_Swallow]

A lot of you probably already know about this,  But I was wondering if anyone could think of any uses for a High Temperature material that won't melt at 4400K or about 7,460 degrees Fahrenheit.

http://gizmodo.com/this-material-wouldnt-melt-even-at-the-center-of-the-e-1720668975

Original article at;

https://news.brown.edu/articles/2015/07/melting

     I was thinking of the obvious, thermal protaction systems and rocket engine linings, but not knowing how fragile this material would be, I figured I'd see if someone else could come up with better uses.

If it is a good conductor a hot chamber for solar thermal rocket engine. Heat the outside with sunlight and let the inside heat the propellant.

[JasonAW3]

Perovskite superconductors were an accidental discovery.

Edit: I read Kelvin when you wrote Celsius. Citation needed, bub.

You know what? You're right!  I did screw up.  it was supposed to be 140 Degrees C or about 149 F!

http://www.superconductors.org/141C136C.htm

Thank you for catching that!

I've spent enough time tilting at pseudoscientific windmills over on the EMDrive thread, but that hardly counts as a credible source for a claim of "hot" superconductivity. If this board is to maintain respectability there need to be standards.

Statements on the linked page such as this:

"While the scientific community continues to pretend that room-temperature superconductivity has not yet been achieved, Superconductors.ORG herein reports the discovery of room temperature superconductors number 25 and 26 - further advancing the world record for high Tc."

firmly place that author in tin-hat territory.

Back on topic, quantum chemical methods do not have the strong predictive power as, say, CFD and other classical physics simulations. This is based on my own experience with molecular quantum chemistry and my discussions with people working in solid-state theoretical chemistry. I would suggest taking these theory papers with a huge grain of salt until they are backed up with experiments.

I'll put it bluntly, I found about 3 or four different site, including a few university sites that confirmed this result.  As I currently have more pressing matters that I have on my agenda over the next few days,I don't currently have the time nor patience to do your research for you.look up the sources yourself if you wish to refute this or simply wait until Monday when I have more time to discuss this.

     As mentioned in previous articles, this material was made with a "layer cake" technique under a pure O2 atmosphere under high pressure.  Unfortunately, the material at present is very fragile so only a few samples were made for testing.

     I suspect that the main reason that this hasn't really hit the press is that because of its fragility and difficulty to make, (as well as being so recent) it current has no real uses that it can be put to.  Scaling up a process for manufacturing such a material would be expensive, but useless if it keeps crumbling to dust.

[Tetrakis]

I don't want to get too off-topic here, but if you are going to start making bold claims about room-temperature superconductivity like that, you need to provide some credible sources. Certainly more credible than university PR and a website. You can't just make strong assertions like that and expect to be taken seriously.

Back on topic, this is an interesting paper. Perhaps with enough time, a synthetic lab will be inspired by it and make the compound. The hafnium and zirconium borides were studied in depth in the mid-20th century for applications as ultra-high temperature ceramics for aerospace applications, and then later in the 80s and 90s for use in hypersonic wing leading edges. Its just too bad that this class of boride ceramic tends to be so brittle and oxidatively unstable at >3000 degrees, precluding most of the more exciting applications.

[john smith 19]

Back on topic, this is an interesting paper. Perhaps with enough time, a synthetic lab will be inspired by it and make the compound. The hafnium and zirconium borides were studied in depth in the mid-20th century for applications as ultra-high temperature ceramics for aerospace applications, and then later in the 80s and 90s for use in hypersonic wing leading edges. Its just too bad that this class of boride ceramic tends to be so brittle and oxidatively unstable at >3000 degrees, precluding most of the more exciting applications.

They do state the next goal (by another team) is synthesis. And 3000c is pretty impressive, up with RCC, if it can be made in lighter and/or more ductile sections.

TBH I've never really liked the hype around Carbon Carbon composites. IRL outside a vacuum furnace (where there performance is impressive) their TPS ability depends entirely on the quality and resilience of the anti oxidation coating. That sets the real limits on RCC before it turns into "designer coal."

I'm not sure the sharp leading edge programmes of the 90's and 00's looked at combined nitride carbides to make any comment on how good this will be. Hafnium does ring a bell.

I think the impressive thing is that the combination gives an MP greater than Tungsten but at (in principal) much lower density.

[Asteroza]

The basic concept behind the material though, a high entropy solid phase with low entropy differential between solid and liquid phases, as found in existing synthesized high temperature materials, seems valid and possibly usable elsewhere. Additionally the recent work in high entropy metal alloys may be applicable here as well.

[Paul451]

[140°C superconductor]
I suspect that the main reason that this hasn't really hit the press is that because of its fragility and difficulty to make, (as well as being so recent

It isn't recent. The same guy (it's one guy, Joe Eck) has been making the same claims for over a decade. Every few months he reports another above-room-temp variant. It's not that the "material is fragile", it's that it doesn't exist as an actual superconductor. What Eck is doing is measuring slight twitches, of a fraction of a percent, in electrical resistance and/or magnetic response, which he then claims is the equivalent of a Meissner transition in superconducting grains (or grain-boundaries) within the material.

Critics say Eck is just overreacting to the mundane noise of thermal expansion/contraction in the materials. Ie, wishful thinking by someone who's spent way to long looking at his own data.

Hey, who knows, maybe Eck is right. But even if the effect is real, this is still not an "above room temperature superconductor". It's not that it's fragile, it's that it's limited to micro-structures buried within a bulk material, which can't be separated from the bulk material, and which Eck has never been able to amplify (to increase the proportion of material that displays the effect.) Eck keeps coming up with new mixes, and keeps saying the transition temp is increasing (up to the 140°C you quoted), but he has never expanded the size of the effect within his materials.

Hope that makes it clearer why people like Tetrakis dismiss it. Lone researcher claiming to have revolutionised physics (except for suppression by "lamestream labs".) Fringe. Unreplicated. Fitting curves by eye. "Signal" entirely inside of margin of error, with no improvement in S/N in decades.

[Stormbringer]

I don't want to get too off-topic here, but if you are going to start making bold claims about room-temperature superconductivity like that, you need to provide some credible sources. Certainly more credible than university PR and a website. You can't just make strong assertions like that and expect to be taken seriously.

Back on topic, this is an interesting paper. Perhaps with enough time, a synthetic lab will be inspired by it and make the compound. The hafnium and zirconium borides were studied in depth in the mid-20th century for applications as ultra-high temperature ceramics for aerospace applications, and then later in the 80s and 90s for use in hypersonic wing leading edges. Its just too bad that this class of boride ceramic tends to be so brittle and oxidatively unstable at >3000 degrees, precluding most of the more exciting applications.

I'll just drop this right here:

http://phys.org/news/2015-08-team-sample-stanene.html

it's supposed to be a room temperature super- ...well you know.