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Metal Without Mining

magratheametals.com

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Re: Metal Without Mining

#6
post #2

Isn't Magnesium highly flammable/explosive? How do you protect parts made from this metal?

Mainly in elemental form. When properly alloyed its explosive/flammable properties can be mitigated.

Re: Metal Without Mining

#7
post #2

Isn't Magnesium highly flammable/explosive? How do you protect parts made from this metal?

https://en.wikipedia.org/wiki/Magnesium_wheels#Common_issues

I've seen this assurance before that magnesium flammability isn't a practical concern, usually just saying fires are "rare", but never any real information as to why. From that link it sounds like there are alloys that maybe preserve the desirable properties of the metal but aren't as flammable as elemental magnesium. Anybody know more about that? Why it works? How well?

Re: Metal Without Mining

#8
I love ideas around extracting minerals from seawater since there is just so much. e.g. estimated 4.5B tons of uranium in seawater, ~1000x higher than land sources. Pretty much everything is dissolved in there, but the energy requirements are insane

Re: Metal Without Mining

#10
post #2

Isn't Magnesium highly flammable/explosive? How do you protect parts made from this metal?

Magnesium parts are already in widespread use. The covers you see on the sides of motorcycle engines/transmissions are often magnesium.

In solid form the risk is mitigated because there isn't enough surface area for the reaction with oxygen, it's the powder/shavings that are a concern. You can actually weld magnesium parts without it igniting.

Reading up on it a little more - it seems with enough heat solid magnesium can start a self-sustaining burn without oxygen. I wish I could find a laymans explanation of the difference between oxygen fueled magnesium powder fire and self sustaining. Must take an awful lot of heat if a welding arc isn't hot enough to cause this.

Edit: Also think of steel wool and how well it burns, but a block of steel not so much.

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