For Moon Missions, Researchers Test a 3D-Printable, Waterless Concrete (technologyreview.com) 14
"If NASA establishes a permanent presence on the moon, its astronauts' homes could be made of a new 3D-printable, waterless concrete," writes MIT Technology Review. "Someday, so might yours.
"By accelerating the curing process for more rapid construction, this sulfur-based compound could become just as applicable on our home terrain as it is on lunar soil..." Building a home base on the moon will demand a steep supply of moon-based infrastructure: launch pads, shelter, and radiation blockers. But shipping Earth-based concrete to the lunar surface bears a hefty price tag. Sending just 1 kilogram (2.2 pounds) of material to the moon costs roughly $1.2 million, says Ali Kazemian, a robotic construction researcher at Louisiana State University (LSU). Instead, NASA hopes to create new materials from lunar soil and eventually adapt the same techniques for building on Mars.
Traditional concrete requires large amounts of water, a commodity that will be in short supply on the moon and critically important for life support or scientific research, according to the American Society of Civil Engineers. While prior NASA projects have tested compounds that could be used to make "lunarcrete," they're still working to craft the right waterless material.
So LSU researchers are refining the formula, developing a new cement based on sulfur, which they heat until it's molten to bind material without the need for water. In recent work, the team mixed their waterless cement with simulated lunar and Martian soil to create a 3D-printable concrete, which they used to assemble walls and beams. "We need automated construction, and NASA thinks 3D printing is one of the few viable technologies for building lunar infrastructure," says Kazemian.
Beyond circumventing the need for water, the cement can handle wider temperature extremes and cures faster than traditional methods. The group used a pre-made powder for their experiments, but on the moon and Mars, astronauts might extract sulfur from surface soil.
Kazemian and his colleagues recently transferred the technology to NASA's Marshall Space Flight Center for further testing...
"By accelerating the curing process for more rapid construction, this sulfur-based compound could become just as applicable on our home terrain as it is on lunar soil..." Building a home base on the moon will demand a steep supply of moon-based infrastructure: launch pads, shelter, and radiation blockers. But shipping Earth-based concrete to the lunar surface bears a hefty price tag. Sending just 1 kilogram (2.2 pounds) of material to the moon costs roughly $1.2 million, says Ali Kazemian, a robotic construction researcher at Louisiana State University (LSU). Instead, NASA hopes to create new materials from lunar soil and eventually adapt the same techniques for building on Mars.
Traditional concrete requires large amounts of water, a commodity that will be in short supply on the moon and critically important for life support or scientific research, according to the American Society of Civil Engineers. While prior NASA projects have tested compounds that could be used to make "lunarcrete," they're still working to craft the right waterless material.
So LSU researchers are refining the formula, developing a new cement based on sulfur, which they heat until it's molten to bind material without the need for water. In recent work, the team mixed their waterless cement with simulated lunar and Martian soil to create a 3D-printable concrete, which they used to assemble walls and beams. "We need automated construction, and NASA thinks 3D printing is one of the few viable technologies for building lunar infrastructure," says Kazemian.
Beyond circumventing the need for water, the cement can handle wider temperature extremes and cures faster than traditional methods. The group used a pre-made powder for their experiments, but on the moon and Mars, astronauts might extract sulfur from surface soil.
Kazemian and his colleagues recently transferred the technology to NASA's Marshall Space Flight Center for further testing...
How much will it cost in terms of energy? (Score:2)
To extract sulphur from lunar rock?
Re:How much will it cost in terms of energy? (Score:4, Interesting)
I dont see how it is even necessary.
If it were me, I would not consider sulfur at all. I would have 3 machines there:
1) mobile glass pot furnace
2) rock crusher
3) laser based sintering system to do the 3d printing.
The minerology of the moon is significantly composed of silicon oxides and aluminum/magnesium oxides. This means it can be turned *DIRECTLY* into mullite glass.
It is rather energy expensive (and thus bad for the laser) to do this directly with just the printer robot. However, once glass is made, it has a SIGNIFICANTLY lower melting point than the initial crystallized minerals used to make it. Melting it in an induction pot furnace, cooling it, then smashing it into smalt mix powder, would provide ample binder for use with the laser sintering robot. It could be mixed with the raw regolith as a bulk filler, same as with the sulfur based concrete idea.
There is no soil (Score:1)
Re: (Score:2)
It's more like a bunch of micro knifes that scratch and cut like hell rather than regular earth dust.
But on the other hand, there's low gravity and Helium-3 there, which are pretty useful.
If they are heating it up that hot anyway.. (Score:3)
Lunar regolith is composed of a significant fraction of alumium oxide and silicate mineral, meaning it can be thermally fused into mullite glass.
https://www.lpi.usra.edu/publi... [usra.edu]
https://www.nature.com/article... [nature.com]
If they are heating that shit up with a thermal source anyway, why carry the sulfur up there in the first place?
Martian regolith is more... varied... in its composition. I can see the need to consider bringing a binder up with the mission to get started...
But the moon?
Just laser sinter that shit in-situ.
Re: (Score:1)
Lunar regolith is composed of a significant fraction of alumium oxide and silicate mineral, meaning it can be thermally fused into mullite glass.
https://www.lpi.usra.edu/publi... [usra.edu]
https://www.nature.com/article... [nature.com]
If they are heating that shit up with a thermal source anyway, why carry the sulfur up there in the first place?
Martian regolith is more... varied... in its composition. I can see the need to consider bringing a binder up with the mission to get started...
But the moon?
Just laser sinter that shit in-situ.
Given the amount of Iron on Mars, couldn't we use it instead?
Re: If they are heating it up that hot anyway.. (Score:2)
Re: Oh give it a rest already (Score:3)
Re: Oh give it a rest already (Score:2)
Probably not on Earth. (Score:2)
Made from faux Martian and lunar soil, a new sulfur-based compound could also lead to faster construction on Earth.
I find it unlikely that anything based on sulfur is going to work on Earth. I'm not a chemist so I can't say for sure but I have the sneaking suspicion that it may smell of sulfur as it breaks down.
It could benefit construction on Earth, too. Kazemian sees the new material as a potential alternative for traditional concrete, especially in areas with water scarcity or a surplus of sulfur. Parts of the Middle East, for example, have abundant sulfur as a result of oil and gas production.
Well there's a great idea, just encourage the production of oil and gas. /s -_-
I am not a space engineer... (Score:2)
But a few questions:
1) this lunarcrete uses molten sulfur as a binder; but S melts at 235F/112C. The surface temp of the moon in day can hit 121C. Um....?
2) while energy on the moon (in the right places) is abundant and effectively limitless, going for a molten product seems...overengineered? The moon's gravity is only 1/6 of Earth's, it would seem to me that compression-blocks (just sifted and maybe doped) of lunar soil would be absolutely adequate for a majority of general-use roles? Particularly when