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Breakthough Makes Transparent Aluminum Affordable

Posted by Soulskill on from the hello-computer dept.

frank249 writes: In the Star Trek universe, transparent aluminum is used in various fittings in starships, including exterior ship portals and windows. In real life, Aluminium oxynitride is a form of ceramic whose properties are similar to those of the fictional substance seen in Star Trek. It has a hardness of 7.7 Mohs and was patented in 1980. It has military applications as bullet-resistant armor, but is too expensive for widespread use.

Now, there has been a major breakthrough in materials science. After decades of research and development, the U.S. Naval Research Laboratory has created a transparent, bulletproof material that can be molded into virtually any shape. This material, known as Spinel (magnesium aluminate), is made from a synthetic powdered clay that is heated and pressed under vacuum into transparent sheets. Spinel weighs just a fraction of a modern bulletproof pane.

11 of 247 comments (clear)

  1. Bullets are OK, but... by houstonbofh · · Score: 5, Insightful

    I would be happy with a chip proof windshield!

    1. Re:Bullets are OK, but... by TWX · · Score: 5, Informative

      Before we ask for this for windshields, we need to see how well it handles regular abrasive friction and small particulates. If it scratches easily then it may require a coating of glass on either side for its hardness (albeit with brittleness) in cases where security needs to go along with aesthetics, like armored car windows and other security windows, such that the owners don't care what happens to the glass layer in an incident but want it to look good before the incident and to remain intact during such incidents.

      I doubt that this will be, by itself, a windshield, and if a windshield made out of this stuff still needs a glass layer, then you're right back to where you were before as far as chipping with debris over a certain size is concerned.

      --
      Do not look into laser with remaining eye.
    2. Re:Bullets are OK, but... by viperidaenz · · Score: 5, Informative

      It's harder than quartz. Says so right in the summary, Mohs scale of 7.7. Glass is in the middle somewhere, depends on the type of glass. Gorilla glass is apparently around 6.5

    3. Re:Bullets are OK, but... by Anonymous Coward · · Score: 5, Funny

      Me? I want an invisible airplane like Wonderwoman's...

      I just want wonderwoman. You can keep the imaginary airplane.

    4. Re:Bullets are OK, but... by Em+Adespoton · · Score: 5, Insightful

      Indeed -- the last thing I want are shards of something with a hardness of 7.7 and razor sharp edges flying around. Think obsidian arrowheads, and then think of something that'll hold an edge even better.

      What I'd like to know about is how flexible the stuff is. Usually, the harder a material is, the more rigid it is -- which means that it is super hard right up to the point where it can't take the stress, at which point it fractures all over the place.

      Safety glass gets around this by 1) being pretty flexible and 2) being a laminate of hard and soft materials, so that when the hard material shatters, it is still bonded to enough of the soft material to avoid (many) sharp edges.

      I wonder what the behavioral properties of a laminate of spinel and lexan would be....

    5. Re:Bullets are OK, but... by Xenographic · · Score: 5, Informative

      > One of the features of safety glass is that when it breaks there aren't (or many) pointy edges created.

      Which kind of safety glass?

      They were talking about windshields, those are laminated glass. That means you have two sheets of ordinary annealed glass (which DOES break into big, dagger-like sharp pieces) with a plastic sheet in between (which prevents those sharp pieces from going anywhere). Presumably, given an appropriate substrate, you could make laminate out of any glass-like sheet.

      The other kind of safety glass is tempered. This causes the glass to be stressed along the edges so that when it does break, it breaks into a million tiny pieces (all of which are very, very sharp). It may also simultaneously pop, especially if hit along the edges. It's less dangerous because the pieces, while sharp, are simply too small to do any real damage even if, say, a piece explodes while you're holding it.

      Source: I worked for a cut & temper operation, I've dealt with all kinds of glass.

  2. ST only needed transparent aluminum for... by starglider29a · · Score: 5, Insightful

    ...the audience to see the whales. I'm sure the whales were comforted seeing the inside of a Klingon Bird-of-Prey~

    1. Re:ST only needed transparent aluminum for... by Burdell · · Score: 5, Informative

      I thought they didn't MAKE transparent aluminum in Star Trek IV, Scotty provided the formula as an incentive to provide plexiglass panels for free (since they had no 1980s cash).

  3. Hello Computer... by captain_nifty · · Score: 5, Funny

    Hello Computer... [no response] oh how quaint [begins rapidly using keyboard]

    I still greet my computer this way sometimes.

  4. Well written by myrdos2 · · Score: 5, Interesting

    I must say, that was an unusually well-written article. Good information level, not dumbed down, and the writer actually sounded like she knew what she was talking about.

    I'm shocked.

  5. Re:Why did it take so long ? by MobyDisk · · Score: 5, Funny

    They did, but it took years to figure out the dynamics of the matrix.

    NICHOLS: Transparent aluminum?
    SCOTT: That's the ticket, laddie.
    NICHOLS: It would take years just to figure out the dynamics of this matrix.
    McCOY: Yes, but you'd be rich beyond the dreams of avarice.