ALITEC Propellant

[Nytrunner]

Only if the cost of the alloy powder can be reduced significantly. It's currently at astronomical levels. I'm going to run the Isp program and see what it says. But it outperformed X in a flight test.

Woo, you aren't kidding! I found 'an' Al-Li alloy poweder and it's ~8$/gram

 

[aerostadt]

Woo, you aren't kidding! I found 'an' Al-Li alloy poweder and it's ~8$/gram

I would think that the alloy should be cheaper. As I recall the ET for the Space Shuttle was made of an Al-Li alloy for a significant weight reduction. Since such an alloy is available, it strikes me as ingenious to try it in a solid propellant. For decades there has been speculation of using lithium or lithium hydride (beryllium hydride, too) in hybrid or solid rockets. I can find it in my old "Rocket Propulsion Elements", by George Sutton (1963). However, lithium and lithium hydride are too reactive to be a serious contender for practical rocket propellants. The Al-Li alloy must be easy to handle if it could be used as a structural component in the ET.

 

[0011001100]

I would think that the alloy should be cheaper. As I recall the ET for the Space Shuttle was made of an Al-Li alloy for a significant weight reduction. Since such an alloy is available, it strikes me as ingenious to try it in a solid propellant. For decades there has been speculation of using lithium or lithium hydride (beryllium hydride, too) in hybrid or solid rockets. I can find it in my old "Rocket Propulsion Elements", by George Sutton (1963). However, lithium and lithium hydride are too reactive to be a serious contender for practical rocket propellants. The Al-Li alloy must be easy to handle if it could be used as a structural component in the ET.

The difference is in the amount of lithium. It is easy enough to find aluminum that contains a couple percent of lithium but this propellant uses an alloy of 20%.

I understand that Na and K would be too reactive themselves but can they be alloyed with aluminum at all? If so maybe it is worth a shot at just testing how they react just to see if they would work.

 

[aerostadt]

I understand that Na and K would be too reactive themselves but can they be alloyed with aluminum at all? If so maybe it is worth a shot at just testing how they react just to see if they would work.

As I discussed in post #27 lithium is desirable because the molecular weight is light. In comparison Na and K have higher molecular weight. Al has been desirable in solid propellants, even though its combustion molecular weight is high in Al2O3, because it has a high heat of combustion raising the combustion chamber temperature and hence the specific impulse. A survey of the thermo-chemical computer runs earlier in this thread show that the Al combustion is giving a high flame temperature while the free hydrogen (low molecular weight) in the exhaust is promoting the Isp. Also, there is a known benefit that aluminum combustion promotes combustion stability in solid propellant rockets.

 

[prfesser]

We made propellants for ejection seat rocket/catapult motors. Density ISP was what we were after.
Lead nitrate as primary oxidizer was used in production motors but a green alternative was what we were seeking. Came up with a replacement with same D-ISP and same burn rate using AP and micron size Zr. Run PEP increasing Zr way past scary.
Works but has manufacturing issues

If Mark says something is way-past-scary, that is a definite NOPE NOPE NOPE NOPE NOPE NOPE NOPE NOPE far as I'm concerned.

I like my fingers, toes, eyes, and other bodily parts just where they are. I already know a number of ways to dismember myself, I don't need any new-and-improved ways.

Best -- Terry

 

[MClark]

I guess it might be a bad thing in most mixers.
Just need an argon purge until Zr is wetted into binder. Nitrogen doesn’t work, still will react! Don’t ask how I know.
Price is a big issue with exotic propellant chemicals. Difficult to make, little demand, not good for anything else.

 

[AeroTech]

There's a lot of good info in here, still valid:

Dan Meyer Report

 

[AeroTech]

Even our cost for AP has gone up like 2-1/2X at a minimum.

I guess it might be a bad thing in most mixers.
Just need an argon purge until Zr is wetted into binder. Nitrogen doesn’t work, still will react! Don’t ask how I know.
Price is a big issue with exotic propellant chemicals. Difficult to make, little demand, not good for anything else.

 

[schworer]

Adranos has received a second $20M round of funding, looks like ALITEC may be showing more promise, at least in a test environment.

https://spacenews.com/adranos-a-sta...ocket-motors-closes-20-million-funding-round/

 

[dhbarr]

From online discussion, it seems that not only is there some lithium added to the aluminum alloy, but there's also some deposition of lithium on the surface as well such that the total amount of lithium involved is a fair bit higher than you'd expect with just admixtures. Supposedly this should allow the aluminum to start burning sooner.