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Super Strong Metal Foam Discovered
MikeChino writes to tell us that a North Carolina State University researcher has discovered what appears to be the strongest metal foam yet, capable of compressing up to 80% of its original size under load and still retain the original shape. The hope is that this amazing material could be used in cars, body armor, or even buildings to absorb the shock from earthquakes. "Metal foam is exactly what you might think – a cellular structure made from metal with tiny pockets of space inside. What makes Rabiei’s metal foam better than others is that she’s been able to make the tiny pockets of space more uniform. And that apparently is what gives it the strength as well as elasticity it needs in order to compress as much as it does without deformation. Many tests are being performed in the laboratory to determine its strength, but so far Rabiei says that the spongy material has 'a much higher strength-to-density ratio than any metal foam that has ever been reported.' Calculations also predict that in car accidents, when two pieces of her composite metal foam are inserted 'behind the bumper of a car traveling at 28 mph, the impact would feel the same to passengers as an impact traveling at only 5 mph.'"
Maybe, maybe not. Elasticity is not the same thing as softness... steel is pretty elastic, but you don't necessarily want a face full of it in a car wreck. OTOH, landing in a bed of inelastic potato chips wouldn't be particularly painful (though it would be itchy).
Airbags and bumpers serve two entirely different purposes.
If this material lives up to the hype (unlikely), your next car will feature both items.
I'm curious to know more about the 28mph -> 5mph assertion. That stat was given to the media because it sounds impressive (grant guff), but how does it compare to the deceleration of a traditional auto bumper.
You know what’s ignored and missing in this discussion?
The question of what the spheres are filled with!
Because they are certainly not “filled” with a vacuum.
But I think there got to be cool properties and applications, when you fill them with something else than air.
Any sufficiently advanced intelligence is indistinguishable from stupidity.