Talk:Electrical Conductors

Element	Resistivity @ 20°C	Density (~ r.t.)	Availability	Highland	Lowland
Silver	15.87 nΩ·m	10.490 g·cm⁻³	Unknown	Unknown	Unknown
Copper	16.78 nΩ·m	8.960 g·cm⁻³	Unknown	Unknown	Unknown
Gold	22.14 nΩ·m	19.300 g·cm⁻³	Unknown	Unknown	Unknown
Aluminum	26.50 nΩ·m	2.700 g·cm⁻³	Yes	133,000	69,700
Magnesium	43.90 nΩ·m	1.738 g·cm⁻³	Yes	45,500	57,600
Sodium	47.70 nΩ·m	0.968 g·cm⁻³	Yes	3,100	2,900
Iron	96.10 nΩ·m	7.150 g·cm⁻³	Yes	48,700	132,000
Chromium	125.00 nΩ·m	7.860 g·cm⁻³	Yes	850	2,600
Titanium	420.00 nΩ·m	4.506 g·cm⁻³	Yes	3,100	31,000
Manganese	1440.00 nΩ·m	7.210 g·cm⁻³	Yes	675	1,700
	Lower # => better	r.t. = room temperature		ppm by weight	ppm by weight

Thinking Moon

The Sodium entry is a good example of thinking Moon. That is, looking at ideas that are insignificant when used on Earth but could really save the day when used on the Moon. It does take a rather long scenario to show how Sodium could be used, but this is part of the process needed to compare complicated technical ideas.

--Jriley 13:25, 11 May 2007 (UTC)

Indeed ISRU is important.

I can't see sodium being much use as a conductor inside a habitat due to it's potential for interaction with condensation. Neither can I see much use for NaK in a hab, though that might have uses outdoors.

I've forked Sodium Scenario to it's own article, partly because it deserves an article and partly because this page is intended primarily as a fact resource for other articles.

-- Mdelaney 19:26, 11 May 2007 (UTC)

The only problem I see is that sodium/potassium may not be suitable for buried wires, as described in the Sodium Scenario, as they can be easily scooped with a spoon or cut with a knife. Even if the wire is re-enforced with fibers and an iron core, malleability of the conductive layer could prove to be an issue in high use areas. Excavations and geologic settling would need to be very closely monitored. Long term studies of this kind of buried wire combo may have very interesting results. Would Na and K slowly mix and produce NaK? Would there be enough heat or tension to meld them together? How would the wire deform under varying subterranean pressures? I also cannot help my curiosity about the rate of loss experienced by bare cable buried in lunar regolith, as it will be interesting to see what effects the nano-phase surface iron may have on an uninsulated circuit. How could all of the above effects be mitigated? Oh, what I would give for a bag of mare simulant and a couple of vacuum chambers in a real lab right about now.

Jarogers2001 17:22, 12 May 2007 (UTC)

I thought they got somewhat cold winters where you live. Have you never seen condensation on windows and walls in winter? (Not usually prevalent in modern homes, but was quite a problem in older stone, brick and block buildings in much of Europe)

Luna's not very cold, but it's not very warm underground either, certainly not warm enough to eliminate the possibility of condensation. So I don't think sodium is suitable for indoors. Outdoors there's the problem of the daytime heat, more than enough to melt sodium.

If you're going to go to the trouble of using an iron core, I don't think sodium offers enough of an advantage over just using iron on it's own. And remember, they only use conductive skins to mitigate skin effect, something that's not particularly bad over relatively short spans at high voltage and low frequency. Basically your common HT cable on Earth is steel, they just put an aluminum skin on it to reduce losses.

Technically these two posts should be moved to Talk:Sodium_Scenario. If you move yours, I'll move mine. Using export - import isn't worth the headache for two posts. :)

-- Mdelaney 01:25, 13 May 2007 (UTC)

Sodium

Sodium Abundance

Having looked around I'm only seeing Sodium in the 3k ppm range or listed in compounds that have % occurrences of ~0.5%. Could you cite your sources supporting said abundance of Sodium?

-- Mdelaney 19:27, 11 May 2007 (UTC)