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

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.

Comments

Navy? Warships?

[idontgno]

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.

Re:Navy? Warships?

[TWX]

Fun fact... We bought a barbecue grille several years ago that we really liked. Used it for about year before we got a recall notice. We figured that there are three reasons to issue a recall; the product has a minor flaw that's too much of a pain for the manufacturer to correct in the field so it's cheaper to recall the product, or stupid people are hurting themselves by failing to follow directions or otherwise use the product in a safe fashion so it's just easier to recall the product (think lawn darts), or the product has a fundamental flaw that makes it unsafe and unrepairable at any reasonable expense.

We're both pretty handy; I work on a lot of machines for fun and my wife has a Bachelor's Degree in Mechanical Engineering from MIT, so we figured if it was the first or second reason for a recall (ie, minor, correctable flaw or else improper usage) we could simply work around the issue and continue to use the grille. When we researched the recall more throughly we discovered that it was the third failure mode; the grille housing itself was made out of magnesium! Several owners had, through the course of cleaning the grille, scraped the oxidized layer off of the inside, exposing fresh magnesium, which ultimately ignited and burned the grille into the pavement. I had just thoroughly cleaned our grille when we got the recall notice but hadn't used it yet, and as we were loading it into the truck to take it back to the store I saw where the metal edge of my brush had gouged through the paint and oxide to expose fresh material.

For all I know they've concocted a magnesium alloy for these ships that's both good at handling the corrosive effects of saltwater (along with magnesium's reactivity) and have managed to mitigate the dangers of exposure to fire or explosion, much in th way that sodium hexafluoride (the gas whose density can lower the pitch of one's voice as demonstrated on Mythbusters many seasons ago) is relatively safe compared to fluorine gas, but I'd still be nervous that some other failure mode hasn't been discovered that could be catastrophic down the road.