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Uncwilly 2022-02-25 03:55

[QUOTE=ixfd64;600698]I'm thinking it would be useful to build rockets with this material. It would either:[/QUOTE]
How does it work at cryogenic temps? Is it lighter than carbon fiber? Rocket Lab's Electron rocket uses carbon fiber. SpaceX went with stainless steel (vs) for Starship for strength at various temps (both cryogenic and heated). The external tank for the space shuttle, the center tank for SLS, and the Falcon 9 use a very lightweight version of Aluminum-Lithium alloy ([URL="https://en.wikipedia.org/wiki/2195_aluminium_alloy"]2195[/URL]). It is much stronger per unit mass than steel.

For non-cryogenic fuels, they tend to be very corrosive (this is why Soyuz has a limited life on orbit.)

ixfd64 2022-02-25 05:36

[QUOTE=Uncwilly;600706]How does it work at cryogenic temps?[/QUOTE]

I tried to do some research on whether this material is susceptible to extreme temperatures, but all my Google searches have turned up nothing so far.

storm5510 2022-02-25 16:04

[QUOTE=Uncwilly;600706]...SpaceX went with stainless steel (vs) for Starship for strength at various temps (both cryogenic and heated). The external tank for the space shuttle, the center tank for SLS, and the Falcon 9 use a very lightweight version of Aluminum-Lithium alloy...[/QUOTE]

My eldest brother was in the USAF during the Vietnam War era. After his return, he often mentioned Titanium as the lightweight metal of choice at the time. It is not an alloy. I suspect the technology to create an alloy like Al-Li did not exist at the time.

BTW, the large burnt-orange section of the SLS, is that a single stage, or two?

kriesel 2022-02-25 16:04

By analogy to 1D polyaramids, melting point would be >500C. Chemical 2D bonding may increase that.
This stuff might make a great ablative heat shield. Or load bearing thermal insulation system for moderate heat to cryogenic, especially if it self orients when foamed and can be coaxed into bonding fractally.
It took some digging, but I finally found a URL with quantitative values for properties, not ratios to other materials.

(Paywalled Nature article, [URL="https://www.nature.com/articles/s41586-021-04296-3"]abstract[/URL] freely available gives ~13. GPa 2d elastic modulus, ~490. MPa yield strength. I estimate density ~1.3 g/cc from steel/6.)

Comparing strength to steel is very problematic, as steels have such a wide range of composition and properties. Contrast for example [URL="https://material-properties.org/what-is-strength-of-carbon-steel-definition/"]cheap[/URL] structural steel with [URL="https://material-properties.org/tool-steel-density-strength-hardness-melting-point/"]tool[/URL] [URL="https://www.techsteel.net/alloy/tool-steel/h11"]steels[/URL] (~500MPa vs. 1.8GPa ultimate tensile strength, ~250MPa vs ~1.5GPa yield strength). Densities vary a bit too. Elastic modulus of steel varies a bit, but typically ~200. GPa, ~16. times higher than for the new 2D plastic.

The 2DPA1 plastic or future formulations to follow might be interesting as a component in a composite face sheet in honeycomb constructions:

thin outer coat of plastic as corrosion inhibitor, strain hardened metal foil, plastic spacer, second metal foil, thin coat as corrosion inhibitor composing one face sheet of a honeycomb layup, to get lots of face sheet buckling resistance and strength at low weight.
Honeycomb materials fail in a variety of ways:
face sheet buckling
sheet/core bond delamination
core crush
corrosion
compressive or tensile yield
(more?)
In high performance high weight penalty applications such as aerospace, one could even consider a compound honeycomb, where the plastic spacer in the sandwich described above is a low core height honeycomb geometry.

This may be like the discovery of the first high temperature superconductor. Decades later we still don't have practical room temperature superconductors, but the floodgates opened on HTSC research and considerable [URL="https://en.wikipedia.org/wiki/High-temperature_superconductivity"]advance[/URL] has been achieved.
Now imagine long needle shaped, thick-walled relative to bore diameter, pressure vessels made of steel or other high strength material, corrosion proofed with something impervious to 270+ MPa of CH[SUB]4[/SUB] and H[SUB]2[/SUB]S (superconductive to +14C), with copper terminations/connections, in an ice bath, or in [URL="https://oceanexplorer.noaa.gov/facts/temp-vary.html"]cold deep ocean[/URL] or deep [URL="https://seatemperature.info/great-lakes-water-temperature.html"]great-lakes [/URL]water, for long distance power transmission at low loss.

[QUOTE=storm5510;600727]he often mentioned Titanium as the lightweight metal of choice at the time. It is not an alloy. I suspect the technology to create an alloy like Al-Li did not exist at the time.[/QUOTE]Titanium is a chemical element. It is commonly used in [URL="https://www.refractorymetal.org/how-is-titanium-used-in-aerospaceaeronautics-applications/"]alloy[/URL] form, such as [URL="https://continentalsteel.com/blog/aerospace-titanium/"]Ti6Al4V[/URL]. Many commercially useful metals have useful strength properties in alloy form and are quite weak in pure form. Aluminum is an example; I've used fairly pure 99.5% aluminum or purer in small wire form as a metal deformable gasket between stainless steel flanges, far more economical than using gold wire and equally effective up to ~150C or higher, 10[SUP]-11[/SUP] Torr vacuum system internal pressure, 1 atmosphere external. Aluminum "Mott" seals are used in very high pressure service such as the oil industry. Under the high localized stresses when crushed between flanges, aluminum wire will cold weld and seal if simply crossed. Iron is another example; [URL="https://royalsocietypublishing.org/doi/pdf/10.1098/rsta.1967.0004"]pure iron[/URL] is weak, while alloyed with a bit of carbon or other elements can be quite strong.

xilman 2022-02-25 18:23

[QUOTE=kriesel;600728]Many commercially useful metals have useful strength properties in alloy form and are quite weak in pure form. Aluminum is an example.[/QUOTE]Tungsten is another. ure tungsten is as malleable as copper. Add <= 1% oxygen, as is found in almost all commercial samples, and at room temperature it is about as brittle as glass. Heat commercial W red-hot and it is also as brittle. A little below that temperature and it is again as easily worked as is Cu. One of my (almost) completely useless skills is to know how to heat tungsten wire so that it can be bent into furnace-heating elements. People either have the skill or they do not. The lab glass-blowing chappie said it was almost impossible to teach it.

Uncwilly 2022-02-25 20:34

1 Attachment(s)
[QUOTE=storm5510;600727]BTW, the large burnt-orange section of the SLS, is that a single stage, or two?[/QUOTE]With the Shuttle that was just a pair of tanks. With SLS it is complicated. Block 1 will have a the tanks and an adapter to the stage above that. The adapter cone is orange, but the second stage is white. The later Block 1B will have a larger diameter second stage that is orange (the colour of the insulation). Block 2 is the same as Block 1B, except the boosters are upgraded.

Dr Sardonicus 2022-05-20 00:43

Boeing's Starliner capsule successfully launched at 6:54 EDT (2254 GMT) May 19.

Starliner is scheduled to dock with the ISS around 7 p.m. EDT (2300 GMT) on Friday, May 20.

chalsall 2022-05-20 01:29

[QUOTE=Dr Sardonicus;606140]Boeing's Starliner capsule successfully launched at 6:54 EDT (2254 GMT) May 19.[/QUOTE]

Yup... I watched it live.

Boeing *needs* this to work. Let us hope they figured out their software issues.

Separately... [URL="https://www.youtube.com/watch?v=3Ux6B3bvO0w"]Musk is working a bit deeper...[/URL]

Uncwilly 2022-05-20 01:56

Don't celebrate too quickly.
[url]https://twitter.com/StephenClark1/status/1527457462240137229[/url]

sdbardwick 2022-05-20 03:01

[QUOTE=Uncwilly;606143]Don't celebrate too quickly.
[url]https://twitter.com/StephenClark1/status/1527457462240137229[/url][/QUOTE]
So, the best Boeing can deliver given enough time and money, is a product where two key systems fail on the qualifying flight. That low ceiling should preclude human-rating, IMO. I'd like to think the ability to produce a 100% functional product needs to be proven. But then again, it is a gov't project, so who knows what and how the key capabilities and performance benchmarks are defined in the contract. Maybe avoidance of RUD prior to docking is enough to pass. Hope there are reserve parachutes aboard for the return trip.

Frustrating that Boeing has fallen so far.

chalsall 2022-05-20 19:33

[QUOTE=sdbardwick;606148]Frustrating that Boeing has fallen so far.[/QUOTE]

Boeing is used to "cost plus" contracts for its rocketry work.

Politicians love these because the contractor makes sure to spread the work across all the various states so everyone can point to the employment opportunities provided.

[URL="https://en.wikipedia.org/wiki/Space_Launch_System"]SLS[/URL] is a perfect example of this. In the false economy of these types of projects, wasted money is actually a good thing. Actually getting the job done is secondary.

Uncwilly 2022-05-20 19:40

[QUOTE=chalsall;606176][URL="https://en.wikipedia.org/wiki/Space_Launch_System"]SLS[/URL] is a perfect example of this. In the false economy of these types of projects, wasted money is actually a good thing. Actually getting the job done is secondary.[/QUOTE]SLS is a jobs program designed to look like a space program. It is doing its job perfectly.

Dr Sardonicus 2022-05-21 03:02

[QUOTE=chalsall;606176]Boeing is used to "cost plus" contracts for its rocketry work.
<snip>[/QUOTE]Boeing's contract for this project [Starliner] is fixed-price. The company has lost hundreds of millions of dollars due to the delays in meeting objectives.

Even so, I haven't heard of any Boeing execs being reduced to picking crusts out of the gutter...

storm5510 2022-05-21 15:39

[QUOTE=sdbardwick;606148]...Frustrating that Boeing has fallen so far.[/QUOTE]

There is a documentary on one of the streaming channels entitled, "The Case Against Boeing." Boeing was always known for its high standards of manufacturing and quality. That is, until the merger with McDonnell Douglas in 1997. Somehow, the exec's from M-D managed to push out the exec's of Boeing. The president of M-D became the new president of Boeing. Boeing was to take over M-D. It was actually the reverse.

When that happened, everything at Boeing changed. No longer was it a quality driven company. It because a profit driven company. Many production corners were cut and thousands lost their jobs. The corporate HQ was moved from Seattle to Chicago. Management didn't want to be bugged by engineers with questions any longer.

Major problems with the 737 Max, after two crashes, brought it all out into public view. Pilots with thousands of hours of flight time refused to fly them. A senator from Oregon began a congressional investigation. Top executives from Boeing were called to testify.

The straw that broke the proverbial camel's back was MCAS. Short for Maneuvering Characteristics Augmentation System. The problem was that pilots had not been told about the addition. Boeing felt it was not necessary to tell them. 737 Max flight manuals made no mention of MCAS other than one item in an alphabetical listing in the very back of the manual.

Boeing was charged with criminal misconduct for misleading regulators but never pleaded guilty to the charges. In the settlement, Boeing paid $2.5-billion with the majority going to airlines and survivors.

Boeing lost their hard earned reputation. This is a permanent stain which will never go away.

Dr Sardonicus 2022-05-21 16:40

[QUOTE=sdbardwick;606148]Maybe avoidance of RUD prior to docking is enough to pass. Hope there are reserve parachutes aboard for the return trip.

Frustrating that Boeing has fallen so far.[/QUOTE]Return trip? I'm more worried about something like the following:[indent][b]The Starliner craft has crashed into ISS. The station and Starliner have been destroyed. All crew lost.[/b][/indent]
The whole point of keeping Boeing on the project is to have more than one way to get astronauts and supplies to the ISS.

A scenario as above would certainly take care of that problem.

masser 2022-07-08 02:32

[QUOTE=masser;582378]Parker Solar Probe still going strong, by last check. Not a surprise, really, considering the success of previous crafts, like Helios 2.[/QUOTE]

[URL="https://en.wikipedia.org/wiki/Parker_Solar_Probe#Timeline"]Perihelion #12 recently.[/URL] Really, quite the remarkable little mission!

Dr Sardonicus 2022-09-05 13:40

[url=https://www.npr.org/2022/09/03/1120742884/nasa-artemis-1-launch-saturday-time-moon-mission-rocket-orion-sls]NASA won't try to launch the Artemis 1 moon mission again for at least a few weeks[/url][quote]CAPE CANAVERAL, Fla. - NASA has delayed any new launch attempt for the Artemis moon mission until at least Sept. 19 after scrapping a planned launch on Saturday.

The decision on Saturday morning was the second time in a week the launch had been postponed.
<snip>
The space agency's first effort to launch this rocket had to be scuttled on Monday morning after a sensor indicated that one of the rocket's four engines didn't seem to be cooling down to the proper temperature of approximately minus-420 degrees Fahrenheit.

After studying the problem and troubleshooting, officials said it's clear the engine was actually fine and a sensor was giving a false temperature reading. "We know we had a bad sensor," said John Honeycutt, program manager for this rocket at NASA's Marshall Space Flight Center in Huntsville, Ala.

Then on Saturday, as crews worked to fuel up the rocket, they repeatedly detected a liquid hydrogen leak that caused them to stop and start the fueling process several times.

NASA made three unsuccessful attempts to repair the leak before falling so far behind schedule that Blackwell-Thompson ultimately [b]waived[/b] [sic] off the launch.
<snip>[/quote]

From [url=https://www.pbs.org/wgbh/nova/transcripts/2610tothemoon.html]To the Moon ([b]NOVA[/b])[/url]:[quote]A. TISCHLER: Some of the people in the headquarters referred to Marshall as the Chicago Bridge and Iron Works, and all of their vehicles were very conservatively designed with safety factors that I think were probably excessive by today's standards at least. However, there's one thing that has to be acknowledged. They worked.

NARRATOR: But von Braun's conservative engineering has a down side. His team works slowly, testing their rockets one stage at a time. At this rate, it will be years before the Saturn 5 is ready. Dr. George Mueller, Director of Manned Spaceflight, sees a way to cut the schedule: test the whole rocket at once, an "all-up" test. Von Braun and his team are aghast.
<snip>
NARRATOR: By 1967, rocket and launch complex are ready. On November 9, at 7:00 am, Rocco Petrone's launch team lights the candle.

ROCCO PETRONE: You count up and at 6 seconds roughly you give the first signal to burn.

CONTROLLER: Five, four - we have ignition -

NARRATOR: When the engines all reach correct thrust, the rocket sends a command: "LET ME GO!" The hold-down arms release. The swing arms retract. The Saturn 5 is on its own.

GEO. MUELLER: You could see the triumph in some of our faces when it actually went off properly.

R.SEAMANS: And I was with Werner and some of his team there, and they said, "We just can't believe it, it all worked!"[/quote]

Dr Sardonicus 2022-09-12 19:23

Jeff Bezos's Blue Origin Shepard 1 booster failed shortly after liftoff September 12, 2022.

The capsule escape system worked.

Uncwilly 2022-09-12 20:46

[QUOTE=Dr Sardonicus;613288]Jeff Bezos's Blue Origin Shepard 1 booster failed shortly after liftoff September 12, 2022.[/QUOTE]Spinning up YT now!

Uncwilly 2022-09-26 20:42

Live video from DART (Double Asteroid Redirect Test) in about 50 minutes:
[YOUTUBE]-6Z1E0mW2ag[/YOUTUBE]

chalsall 2022-09-26 21:00

[QUOTE=Uncwilly;614238]Live video from DART (Double Asteroid Redirect Test) in about 50 minutes:[/QUOTE]

Thanks for the reminder. Now streaming. 29 minutes before the stream goes live...

The game of Pool can be almost as much fun as the game of Go. 8^)

Uncwilly 2022-09-26 21:02

[QUOTE=chalsall;614240]The game of Pool can be almost as much fun as the game of Go. 8^)[/QUOTE]
This is the second move in a game of Go. The dinosaurs saw the first move.

chalsall 2022-09-26 21:25

[QUOTE=Uncwilly;614241]The dinosaurs saw the first move.[/QUOTE]

Allegedly.

chalsall 2022-09-26 21:40

It is an amazing time to be alive!
 
The link 'Willy gave is now live. With raw video.

From two different spacecraft some light-seconds away from us.

One is going to crash into a small body orbiting another small body. The other is going to watch this happen.

And... At the same time, a *whole* lotta observations are going to be done in parallel. Over time.

Detecting orbits can take quite a bit of work and time.

Thank the gods we humans can now do this kind of thing.

Uncwilly 2022-09-26 22:01

[QUOTE=chalsall;614246]From two different spacecraft some light-seconds away from us.[/QUOTE]
Single image. The right frame is the whole field of view. The spacecraft is only sending the bit with the image and the data of where that is within the frame. Cuts data usage. Expect it to go full frame later.
Hosted feed has gone live at:
[YOUTUBE]4RA8Tfa6Sck[/YOUTUBE]

chalsall 2022-09-26 22:39

[QUOTE=Uncwilly;614249]Single image. The right frame is the whole field of view. The spacecraft is only sending the bit with the image and the data of where that is within the frame. Cuts data usage. Expect it to go full frame later.[/QUOTE]

I sit corrected. Always welcome understanding.

I /thought/ there was going to be a CubeSat following along. Ejected in such a way that it did a fly-by rather than intercept.

chalsall 2022-09-26 23:19

That team did the job!
 
I was literally in tears watching that.

An example of what can happen when people work together. Rather than pull each other down.

Crabs in a barrel doesn't scale.

Uncwilly 2022-09-27 00:20

[QUOTE=chalsall;614252]I /thought/ there was going to be a CubeSat following along. Ejected in such a way that it did a fly-by rather than intercept.[/QUOTE]There is that, but it will be a low bit rate return. It has an umpire's view of the event. Expect the first return of the cube sat images tomorrow or the next day.

sdbardwick 2022-09-27 05:20

In case anybody missed it, [URL="https://fallingstar.com/home.php"]ATLAS [/URL] (Asteroid Terrestrial-impact Last Alert System) got some good images. This YouTube is from the ATLAS footage: [url]https://www.youtube.com/watch?v=MPaaDSIS-tY[/url]

LaurV 2022-09-28 02:56

Bruce Willis on board?

With a ton of TNT or something?

If not, no fun... :razz:

xilman 2022-10-11 18:21

Looks like it did something other than kick up a lot of dust.

[url]https://www.bbc.co.uk/news/science-environment-63221577[/url]

LaurV 2022-10-14 10:32

Yep, we changed the direction, like [URL="https://www.youtube.com/shorts/eVDoByntYYs"]Trevor said[/URL], before it was not going in our direction. Now it is... :razz:

Dr Sardonicus 2022-11-16 15:08

1 Attachment(s)
The Artemis rocket launched at 1:47 am EST (0647 GMT) November 16, 2022.

chalsall 2022-11-19 03:10

Space is hard...
 
I happened to come across [URL="https://www.space.com/spacex-starlink-satellite-loss-space-weather-forecast"]this article.[/URL]

Horror vacui.

storm5510 2022-11-29 18:02

[QUOTE=Dr Sardonicus;617930]The Artemis rocket launched at 1:47 am EST (0647 GMT) November 16, 2022.[/QUOTE]

I stayed up to watch as did my 80-year-old brother. He is a USAF veteran of The Vietnam War. I had always wondered how they came up with the name Artemis. Somebody mentioned that in Greek Mythology, Artemis is the twin sister of Apollo. :grin:

Uncwilly 2022-11-29 23:05

[QUOTE=storm5510;618694]Somebody mentioned that in Greek Mythology, Artemis is the twin sister of Apollo. :grin:[/QUOTE]Artemis has been floating around in the SciFi world as a name for the successor for a while.


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