Science News proves that there’s always something new to figure out – in this case, with one of the most common and worked-with metals we know: lead. New research shows after being exposed to high enough pressures, lead becomes stronger than steel:
To study how lead’s strength changed under pressure, researchers rapidly compressed a lead sample by blasting it with lasers at the National Ignition Facility at Lawrence Livermore National Laboratory in California. The pressure within the sample reached about 400 gigapascals — similar to the pressures found within Earth’s core.
The strength of a material characterizes its response to stress — a force applied over a given area. The more stress that a substance can endure before it deforms, the stronger it is. Physicist Andrew Krygier of Lawrence Livermore and colleagues observed how ripples in the lead grew and deformed under the high-pressure conditions. The growth was relatively slow, indicating that the metal was 250 times as strong as lead under normal conditions and about 10 times as strong as high-strength steel.
Calculations suggest that the pressure alters lead’s crystal structure, causing a rearrangement of its lattice of atoms.