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New Magnesium-Alloy Foam From NYU's Nikhil Gupta Floats On Water

Posted by timothy on from the floating-on-sand-is-old-hat dept.

Jason Koebler writes: A new class of magnesium-alloy syntactic foam, which is made out of hollow particles to lower its weight and density is one of the strongest metals for its weight and density ever developed, which makes it ideal for use in boats. Developed by Nikhil Gupta at NYU Polytechnic University, the alloy is 44 percent stronger than similar, aluminum-based foams, and each individual sphere within the foam can withstand pressure of more than 25,000 pounds per square inch before breaking, which is roughly 100 times the pressure exerted by water coming out of a firehose. Gupta's foams are currently used by the Navy and he suspects this one will be ready for use in warships within three years.

3 of 101 comments (clear)

  1. Navy? Warships? by idontgno · · Score: 5, Interesting

    How flammable is this foamed magnesium alloy?

    A warship full of foamed magnesium would go up like a flare. It even incorporates its own oxidizer in the foam, in the air spaces. Unless they're forming the voids with inert gas.

    Unless they've paid some special attention to the flammability issue, a combat vessel made with this stuff would make the Forrestal look like a birthday candle.

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    1. Re:Navy? Warships? by NatasRevol · · Score: 5, Informative

      Science fact: magnesium != magnesium alloy

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    2. Re:Navy? Warships? by ShanghaiBill · · Score: 5, Informative

      Syntactic foams have many very good properties. They use hollow ceramic beads embedded in a metal matrix. The beads are usually filled with an inert gas, most commonly nitrogen, often at far higher than 1 atm pressure. They are not particularly flammable, because the ceramic doesn't burn, and the pressurized N2 released during combustion retards the flame. It is also possible to embed halogenated frame retardants in the beads. They are strong in compression because the foam can absorb shock. They handle compression, tension, and shearing well because the beads inhibit crack propagation, sort of like how a missing link stops a zipper from unzipping. They resist heat conduction and melting better than solid metals. And, of course, they are light.