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Transparent ceramics made with aluminum

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Re: Transparent ceramics made with aluminum

#61

Post by delecti »

emaginniss wrote: post #55
mohaine wrote: post #42

Earlier quoted context omitted.

I don't think they used transparent aluminum in Star Trek IV. I thought they paid for whatever they used (plexiglass?) with the recipe for transparent aluminum. Although it could just be that I'm forgiving the poor writing.

Wouldn't that mean that nobody ever invented it?

No humans maybe.

And if humans were in fact the source of Starfleet's knowledge of transparent aluminum then it'd be an instance of a causal loop, of which there are many examples in fiction.

Re: Transparent ceramics made with aluminum

#62

Post by msumpter »

emaginniss wrote: post #55
mohaine wrote: post #42

Earlier quoted context omitted.

I don't think they used transparent aluminum in Star Trek IV. I thought they paid for whatever they used (plexiglass?) with the recipe for transparent aluminum. Although it could just be that I'm forgiving the poor writing.

Wouldn't that mean that nobody ever invented it?

I believe the story was the person who invented transparent aluminum was the man they approached and just gave him the idea sooner (or maybe this is how he always came up with it, timelines can be funny)

Re: Transparent ceramics made with aluminum

#63

Post by georgeecollins »

I believe the first Apple Newton had transparent aluminium for the screen. I can't find confirmation of that but I remember going to a sales training session for it (long story) and they told people to say the screen was transparent aluminium, like they talked about in one of Star Trek movies.

Re: Transparent ceramics made with aluminum

#64

Post by pwg »

John_KZ wrote: post #2

Saying this is transparent Aluminum is the same as saying Glass is transparent Silicon. It's not, it's just a ceramic.

The title is a reference to a line in the movie "Star Trek IV: The Voyage Home" where Scotty trades the formula for "transparent aluminum" (from the future) in a barter transaction for plexiglass sheets (in the present) that the cast need to achieve their goal in the movie.

https://en.wikipedia.org/wiki/Star_Trek_IV:_The_Voyage_Home

https://en.wikipedia.org/wiki/Transparent_aluminum#Transpare...

Re: Transparent ceramics made with aluminum

#65

Post by jboy55 »

mohaine wrote: post #42
jboy55 wrote: post #37

On a completely separate note, what was the deal with the need for transparent aluminum in Star Trek IV? Looking at the footage, they easily could have made the tank bigger if they just used all of the space available and didn't need to be able to "see" them from outside their tank. All they would have needed the aluminum for is to keep water out of where water shouldn't go and regular aluminum (or other material) wo…

I don't think they used transparent aluminum in Star Trek IV. I thought they paid for whatever they used (plexiglass?) with the recipe for transparent aluminum. Although it could just be that I'm forgiving the poor writing.

Yes, it seems that way from the script. But then, why a transparent material?

(The answer of course is they're building an aquarium tank, and aquarium tanks are see through or have windows into it so humans can spectate. If they wanted to just bring whales back, they probably would have just flooded some crew room.)

Re: Transparent ceramics made with aluminum

#66

Post by kps »

masklinn wrote: post #28
kdumont wrote: post #27

Earlier quoted context omitted.

I believe hardness is actually a bad thing in terms of replacing gorilla glass in phones. It increases the likelihood of shattering when dropped, and is the main reason for sapphire not being adopted.

> It increases the likelihood of shattering when dropped AlON seems significantly tougher than glass as well as being way harder. So it looks to be both more scratch-resistant and more shatter-resistant. > is the main reason for sapphire not being adopted. Do you have sources (actual sources, not Corning fearing for their business) for that?

> So it looks to be both more scratch-resistant and more shatter-resistant.

Refractive index 1.79, Abbe number 58… Why are my eyeglasses not made of this?

Re: Transparent ceramics made with aluminum

#67

Post by [deleted] »

kdumont wrote: post #57
masklinn wrote: post #28

Earlier quoted context omitted.

> It increases the likelihood of shattering when dropped AlON seems significantly tougher than glass as well as being way harder. So it looks to be both more scratch-resistant and more shatter-resistant. > is the main reason for sapphire not being adopted. Do you have sources (actual sources, not Corning fearing for their business) for that?

I'm no materials scientist. I just recall some articles I read when I was curious why I hadn't seen sapphire showing up in phone screens. Here is the first article Google pulls up. http://time.com/3377972/why-apple-didnt-use-sapphire-iphone-... I agree with you that AlON appears to be harder than glass. I just question if that is necessarily a good thing for consumer electronics. I expect we want something that is ve…

[deleted]

Re: Transparent ceramics made with aluminum

#68

Post by nerfhammer »

tim333 wrote: post #12
dbsvsv wrote: post #10

Earlier quoted context omitted.

I don't think in quite understand. You mean they don't let photons to pass through? In which case do electrons in orbit? Or nuclei for example? Or does this need advanced physics knowledge?

Roughly light is electromagnetic radiation and puts force on electrons it comes in contact with. If the electrons are fixed in a non conductor they don't move much and so don't absorb the energy. If they can move as in most metals the force accelerates them and they absorb energy from the radiation, stoping of reducing it.

huh, is this why sometimes metal gets unbelievably hot if left in the sun? but that should be true of any opaque material

Re: Transparent ceramics made with aluminum

#69

Post by dang »

talltimtom wrote: post #24

The deal is that it isn’t aluminium. Seriusly, what’s with the clickbate headline? If you consider everything that contains aluminium atoms in the structure to be actual aluminium, then Saffire is also transparent aluminium. The authors are diliberatly misleading their readers in order to cincrease interest. That’s a shitty thing to do in science even if do have a cool materiale on It’s own merits.

We've updated the title above.

Re: Transparent ceramics made with aluminum

#70

Post by jacquesm »

didgeoridoo wrote: post #58
saiya-jin wrote: post #41

Earlier quoted context omitted.

that doesn't make sense - if that would be the case, the back-emitted photon would have a random vector, not pertaining the same one as original one (thus preserving the picture beyond the sheet of metal). you are stating somehow the direction of photon is preserved when absorbed by electron - absurd idea even for layman physics (not claiming I know how this works, but this can't be the way)

I barely understand even layman-level physics, but it would seem to me that this “absurd” idea is just a natural implication of the conservation of momentum? edit: to all the downvoters of saiya-jin — let the one who has never defended their incorrect intuitions in physics cast the first downvote!

> let the one who has never defended their incorrect intuitions in physics cast the first downvote!

Amen. This stuff is wildly counter-intuitive, we only properly know how mirrors work since we understand the photo electric effect, and even with that understanding it is still quite tricky because it requires insight into how stuff works at a level where direct observation is no longer possible without access to enormous resources.

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