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Lead just got an upgrade. When it is quickly compressed with powerful lasers, the typically weak element gets 250 times stronger, making it tougher than hardened steel.

The difference between strong and weak materials has to do with how the atoms move against one another. When the atoms are arranged so that they can slide across each another easily, like they typically are in lead, the material is soft and pliable. When they cannot move around so easily, like in iron, the material is hard and strong.

Andy Krygier at the Lawrence Livermore National Laboratory in California and his colleagues tested the properties of lead that is quickly pushed to incredibly high pressures using lasers at the National Ignition Facility, also in California.

Applying significant pressure also applies heat, so the researchers had to devise a setup that would allow the lead to reach pressures higher than those in Earth鈥檚 core without melting. They did this using a special gold tube, which had a higher melting point, into which they fired 160 laser beams. Those beams heated up the tube to about 1,000,000掳C, sending a high-pressure shock wave through a sample of lead. At the same time, they measured the lead鈥檚 strength using X-rays.

They found that after a few tens of nanoseconds, once the apparatus had reached its highest pressures, the lead had become 250 times stronger. 鈥淲e can hold it at this pressure just long enough to make a measurement before it explodes,鈥� says Krygier. If it were allowed to decompress instead of exploding from the enormous pressure and heat, the extra strength would go away, he says.

As well as teaching us how materials behave at high pressures, like those inside planets, these sorts of experiments could help create shielding that becomes strong when it is hit. 鈥淒esigning new armour for war-fighters or for tanks or even for satellites that run into small meteors depends on our ability to understand dynamic strength,鈥� says Krygier. 鈥淔rom the point of view of armour, you don鈥檛 actually care how hard the material is until you get shot.鈥�