Synopsis: Metals are supercool

Structural changes in an alloy may lead to a clearer picture of glass transitions in liquid metals.

Some metals stay liquid below their melting temperature (i.e., they can be supercooled) and eventually form a glass when cooled further. While metals are crystalline in solid form, metallic glasses are amorphous. Glassy metals⎯particularly metallic alloys that form thick bulk metallic glasses (BMG)⎯remain an attractive subject of study decades after their discovery.

In an article in Physical Review B, Victor Wessels at the Washington University in St. Louis and his collaborators demonstrate the existence of a rapid ordering process in a supercooled metallic liquid. The group used high-energy x rays from the Advanced Photon Source at Argonne National Laboratory to study structural changes in levitated Cu-Zr alloys as they cool. A rapid chemical and topological ordering of the supercooled liquid begins just 75C below the melting temperature⎯a remarkable 465C above the BMG transition⎯suggesting that the atoms become more ordered well before they finally “slow down” to form a glass.

Cu-Zr alloys, forming BMGs under different conditions, are an ideal system in which to test the physics of glassy metals as they form, pointing us to a clearer understanding of structural ordering prior to the glass transition in liquid metals. – Athanasios Chantis


Announcements

More Announcements »

Subject Areas

Materials Science

Previous Synopsis

Next Synopsis

Related Articles

Focus: A Thermostat that Consumes No Energy
Energy Research

Focus: A Thermostat that Consumes No Energy

Experiments show that a region next to changing hot and cold areas can be maintained at a fixed temperature without consuming energy. Read More »

Focus: Tiny Digital Bits in Ferroelectric Material
Materials Science

Focus: Tiny Digital Bits in Ferroelectric Material

Electrons hitting a ferroelectric material can produce a single digital bit 100 times smaller than the bits in today’s commercial memories. Read More »

Synopsis: Polarons Drive a Magneto-Optical Effect
Magnetism

Synopsis: Polarons Drive a Magneto-Optical Effect

A surprisingly large magneto-optical response occurs when mobile electrons in a cooled material become trapped by their interaction with the surrounding lattice. Read More »

More Articles