OT: Steel is Real

[grognaak]

Elon Musk selects steel over carbon fiber in Starship design:

https://www.popularmechanics.com/space/rockets/a25953663/elon-musk-spacex-bfr-stainless-steel/

[duff_duffy]

Great read!

[mktng]

953 or XCr ?

[Hawker]

Thanks very good read. Thankfully only a few of us here are capable enough to have to worry about re-entry temperatures when we ride.

[old_fat_and_slow]

953 or XCr ?

301 CRES, basically the same material used on early Atlas boosters up until the current Atlas V, and still used on Centaur cryogenic upper stage vehicle. Atlas V changed to an aluminum booster.

[Bentley]

301 CRES, basically the same material used on early Atlas boosters up until the current Atlas V, and still used on Centaur cryogenic upper stage vehicle. Atlas V changed to an aluminum booster.

You are correct that the current Atlas V upperstage is made of aluminum, but its not because stainless steel is an issue.

In the prior incarnation of the Atlas Booster, which dates back more than 50 years, the design was based on a pressure stabilized structure, basically a pressurized balloon. It was and still is a very efficient design. The structure was a stainless steel shell, about 1/2 the thickness of a dime that would be pressurized so that it would support not only its own weight but the weight of the payload above.

This design required that the upperstage (Centaur) be either pressurized or put into "stretch" to assure that it did not collapse on itself.

Over-time, it was determined that moving away from this "efficient" design was overcome by the ability to manufacture lighter structures (with aluminum) that did not require the additional care and feeding of the optimized structure.

I would add that its not entirely true that stainless steel is not used in todays rockets, as you know, aluminum and titanium are very capable materials but they have roughly 70% the strength of steel. Steel, primarily Stainless Steel is used in areas of high load/stress. I am guessing from the photos I have seen that Elon is using more Stainless Steel than typically has been used in the past. His new "Starship" looks like it has a metallic fairing, I had assumed Aluminum (Aluminum is a commonly used fairing material) but I am guessing it may be Stainless Steel which would be different.

[bigbill]

Did a community relations project for the State Department in Tivat, Montenegro in 2007. I had a full rack of 308 stainless piping that was for training (practice welding) and no longer needed. We built swingsets in the city park with the piping. Stack of dimes welds and backing rings, those things were nuke proof. Why not rockets.

Before I took this job in AZ, I had been recruited for Blue Origin to work out in west Texas at their spaceport. I just couldn't handle the thought of living in Van Horn, Texas and having a 45 minute gravel road commute each day.

[grognaak]

Thanks very good read. Thankfully only a few of us here are capable enough to have to worry about re-entry temperatures when we ride.

If a cyclist burns up in the atmosphere, would you call it a killer ride? :)

[dancinkozmo]

wonder if the steel tariffs are applicable in space ?

[Mark McM]

wonder if the steel tariffs are applicable in space ?

Why do think that the President announced the creation of a new Space Force?

[mt2u77]

You are correct that the current Atlas V upperstage is made of aluminum, but its not because stainless steel is an issue.

In the prior incarnation of the Atlas Booster, which dates back more than 50 years, the design was based on a pressure stabilized structure, basically a pressurized balloon. It was and still is a very efficient design. The structure was a stainless steel shell, about 1/2 the thickness of a dime that would be pressurized so that it would support not only its own weight but the weight of the payload above.

This design required that the upperstage (Centaur) be either pressurized or put into "stretch" to assure that it did not collapse on itself.

Over-time, it was determined that moving away from this "efficient" design was overcome by the ability to manufacture lighter structures (with aluminum) that did not require the additional care and feeding of the optimized structure.

I would add that its not entirely true that stainless steel is not used in todays rockets, as you know, aluminum and titanium are very capable materials but they have roughly 70% the strength of steel. Steel, primarily Stainless Steel is used in areas of high load/stress. I am guessing from the photos I have seen that Elon is using more Stainless Steel than typically has been used in the past. His new "Starship" looks like it has a metallic fairing, I had assumed Aluminum (Aluminum is a commonly used fairing material) but I am guessing it may be Stainless Steel which would be different.


So your saying my next bike could be made from extra thin-walled pressurized stainless steel. Hold my beer while I pump up my bike frame!