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Aluminum foil (2021)

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Re: Aluminum foil (2021)

#21

Post by wolfi1 »

nyeah wrote: post #14
IshKebab wrote: post #3

This is pretty much just rambling about how amazing aluminium foil is because it's so thin and that might enable all sorts of wonderful imaginary applications. Very HN. It's aluminium foil.

What's really thin is the oxide layer on the surface https://en.wikipedia.org/wiki/Anodizing When exposed to air at room temperature, or any other gas containing oxygen, pure aluminium self-passivates by forming a surface layer of amorphous aluminium oxide 2 to 3 nm thick,[4] which provides very effective protection against corrosion. Aluminium alloys typically form a thicker oxide layer, 5–15 nm thick, but tend to b…

it usually is not only aluminium oxide but a mixture of aluminium oxide and aluminium hydroxide if it is normal (read: moist) air

Re: Aluminum foil (2021)

#23

Post by jstanley »

1970-01-01 wrote: post #16

>Alternatively, though, it might be possible to stiffen the foil by making the equivalent of corrugated cardboard out of it, maybe using aqueous boric acid (US$1.70/kg according to Potential local sources and prices of refractory materials) or borax as the glue. The surface tension of water is ample to hold aluminum foil in place until the water dries. Hello Amazon? Billion dollar idea here. This needs more attention…

I don't know about corrugated aluminium, but aluminium honeycomb is definitely a thing: https://www.easycomposites.co.uk/aluminium-honeycomb

Re: Aluminum foil (2021)

#24

Post by InitialLastName »

1970-01-01 wrote: post #16

>Alternatively, though, it might be possible to stiffen the foil by making the equivalent of corrugated cardboard out of it, maybe using aqueous boric acid (US$1.70/kg according to Potential local sources and prices of refractory materials) or borax as the glue. The surface tension of water is ample to hold aluminum foil in place until the water dries. Hello Amazon? Billion dollar idea here. This needs more attention…

That would be hell on everybody's box-cutters (and fingers). I already cut myself too often on shipping boxes.

Re: Aluminum foil (2021)

#25

Post by jstanley »

> 50¢/m² is 50¢/kWp in a solar concentrator, or 0.05¢/Wp, which is noticeably cheaper than photovoltaic cells, currently around 18¢/Wp, 360 times more expensive.

A photovoltaic cell is a solar panel, and a piece of aluminium does nothing, am I missing something here?

Re: Aluminum foil (2021)

#26

Post by bluGill »

1970-01-01 wrote: post #16

>Alternatively, though, it might be possible to stiffen the foil by making the equivalent of corrugated cardboard out of it, maybe using aqueous boric acid (US$1.70/kg according to Potential local sources and prices of refractory materials) or borax as the glue. The surface tension of water is ample to hold aluminum foil in place until the water dries. Hello Amazon? Billion dollar idea here. This needs more attention…

aluminum foil is generally not something you can recycle. Not that it can't be recyled, but the oxide to pure aluminum ratio is high and so you don't gain much since you need all the energy of refining in the first place to get back to something usable.

Amazon needs stronger boxes than foil anyway. Cardboard is likely best for them.

Re: Aluminum foil (2021)

#27

Post by Sharlin »

Aluminum is honestly a miracle material that has no business being as inexpensive as it is (of course, this is only since the invention of the Hall–Héroult process, before which aluminum was one of the most expensive metals known despite making up ~8% of the crust).

Re: Aluminum foil (2021)

#28

Post by bluGill »

whynotmaybe wrote: post #13
Forgeties79 wrote: post #10

Earlier quoted context omitted.

You sound like someone who hasn't explored the upper limits of what aluminum foil can solve!

Has a kid, my mom used to pack my lunch in aluminium foil and everyday was a challenge of trying to make the perfect aluminium ball and throw it in the trashcan[1] on the first try! 1. Recycling was a vague concept in the 80s & 90s

Your local recycler probably doesn't want al foil even today when recycling is a big thing.

Re: Aluminum foil (2021)

#29

Post by badc0ffee »

It's non-toxic and food safe, and yet a significant number of people on the internet still act like it's poison that will give you Alzheimer's. I wonder how many of those people touch their lips to the lid of an aluminum beverage can. Or how they might bake a lasagna at home.

Re: Aluminum foil (2021)

#30

Post by cdu1 »

jstanley wrote: post #25

> 50¢/m² is 50¢/kWp in a solar concentrator, or 0.05¢/Wp, which is noticeably cheaper than photovoltaic cells, currently around 18¢/Wp, 360 times more expensive. A photovoltaic cell is a solar panel, and a piece of aluminium does nothing, am I missing something here?

I think the implication is you can use it to reflect additional light onto your photocell, improving the power output for a smaller cost than purchasing an additional cell.
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