Liquid Material becomes Solid in Magnetic Field

FortKnox writes: "Cool cool stuff, here. This Y! article talks of a substance that can morph between liquid and solid by the presence of a magnetic field. Now this is something you can make into a cool toy!"

FP

[FortKnox]

First post on my own article. Feel the karma burn ;-).

But seriously, could you imagine what kind of toys your children could play with if this stuff became commercial??

Toys.

[Christopher Thomas]

But seriously, could you imagine what kind of toys your children could play with if this stuff became commercial??

As the article points out, you can make fluids like this very easily - just dump a bag of iron filings into a glass of vegetable oil. It isn't pretty, and it dries out eventually, but wave a strong magnet around the jar and you can get all kinds of fun effects.

Beyond just playing with a jar of it, though, I don't really see how magnetically-sensitive fluids would be used in toys. If you see a miraculous application, feel free to enlighten me (or to run off and make a bundle on it :)).

Re:FP

[SaXisT4LiF]

Is this really big news? I recall having as a kid, a Ghostwriter. It was kind of like a Magna Doodle (the more popular toy) except it used a fluid instead iron fillings. The fluid would densen on the plastic surface when you put a magnet up to it, and stick there until you shook it up. It was never completely solid, but it was a step towards such a substance. I don't think it's in production anymore...

The reason I remember it, is because it was still laying around the house when Terminator 2 came out and I *REALLY* wanted to make one of those liquid metal robots out it (a smaller one of course). When I see one of those going into production I'll be excited.

this stuff rocks

[NaturePhotog]

This sounds very cool. I'd heard about for use in shock absorbers. Not for the toy potential (seems like it would be hard to get into toy form), but because of the other possibilities described:

• Braille that can be scrolled and amended as easily as text on a monitor
  
• creating molds that can be reconfigured to manufacture different machine parts in a pinch
  
• stabilizing leg brace for the elderly or disabled
  
• controlling the movement of remote-controlled suits
  
• landing gear that adapt "automatically and instantaneously to the local geo-technical conditions of the landing site"
  
• simulating the resistance of human flesh for VR practice of surgery
  

The weight of magnets is problematic for any space-based applications that have to be launched, but pretty cool earth-bound applications to start with.

Of course, for those who are looking for the pr0n angle:

there's even been a U.S. patent granted for an MR "penile prosthetic."

Diliente Colloids

[tolan's my name]

..is it as fun [or messy] as the classic cornflour and water.

Low-tech is the way to go for you cross-physical-states materials.

Re:Diliente Colloids

[Christopher Thomas]

..is it as fun [or messy] as the classic cornflour and water.

It's more fun and more messy, if my own experiences were any guide.

Fun because it will do _very_ neat things if you wave a magnet under the jar - you get a spike of material building up that follows the magnetic field lines. Use multiple magnets, and you can get even wierder-looking effects.

Messy because, being oil-based, you can't just wipe it up with a wet cloth. It also won't dry out when you spill drops of it, like cornstarch does. You'll have to wipe it up with a wad of paper towels and then thoroughly wash the area with soap before it'll come clean. Think back to the last time you spilled a cup of vegetable oil when baking for some idea of how much "fun" this is.