Credit: Image courtesy of Carnegie Institute of Washington, as appearing in Nature Communications.
How metals melt at high temperatures and pressures was clarified with a new x-ray scattering technique. A metal is sandwiched between two high-pressure diamond anvils. A laser melts the sample (right), while the structure is monitored with x-ray diffraction. The metal microstructure (green granular structure and yellow heated regions) at different temperatures is shown schematically on the left. Following the laser pulse, the initial grains grow before melting. (TM is the melting temperature.) Small grains form when the molten metal refreezes after rapid cooling (quenching).