A new study has uncovered the importance of the structure of atomic rings in glasses, revealing how their stability affects the glass's properties and transition temperature. This progress in understanding the molecular dynamics of glass can help design better glass products for high-performance applications.

Glass is increasingly used in a variety of high-performance applications, including consumer and industrial applications, military and avionics, and coatings and optical products. Given the stringent precision requirements for products such as mobile phones and jet aircraft, it is critical that the glass substrate retains its shape throughout the manufacturing process.

Corning Incorporated, a manufacturer of innovative glass, ceramics and related materials, has invested significant resources in studying the stability of different types of glass. Recently, Corning researchers discovered that understanding the stability of atomic rings in glass materials can help them predict the performance of glass products. This ability is important because the most widely used glass is silicate glass, which is made of rings of atoms of different sizes connected in a three-dimensional manner.

Neutron scattering experiment

In neutron scattering experiments at the Department of Energy's Oak Ridge National Laboratory, ORNL and Corning Incorporated scientists found that as the number of smaller, less stable rings of atoms in a glass increases, the glass's instability, or liquid brittleness, increases. Neutron experiment results published in Nature Communications reveal a clear correlation between the mid-range atomic ring structure of silicate glasses and their liquid brittleness. When molten glass cools to its glass transition temperature, its viscosity changes significantly. Under a certain temperature change, the viscosity change of a more brittle liquid will be greater.

Scientists at Oak Ridge National Laboratory and Corning Incorporated found that as the number of smaller, less stable rings of atoms in a glass increases, the glass's instability, or liquid fragility, increases.

"Previously, scientists have not understood the driving mechanisms of glass transitions," said Ying Shi, corresponding author of the study and a research associate at Corning Incorporated. "It was unclear why certain types of glass solidify faster or slower."

Shi and her collaborators from Corning Incorporated, UCLA, and the University of Oxford worked with scientists at the NOMAD neutron diffractometer beamline at ORNL Spallation Neutron Source to study aluminosilicate glasses commonly used in industry.

Using the recently developed and validated neutron scattering data analysis tool RingFSDP, the team identified key patterns from the collected data, revealing the relationship between the brittleness of the liquid in the glass and the stability of its atomic rings.

RingFSDP is a free, open-source program developed by scientists from Corning Incorporated and ORNL to study the atomic ring structure of silicate glasses. It derives the ring size distribution in silicate glasses from the shape of the first sharp diffraction peak in neutron diffraction data.

"Relating the glass transition temperature range to the fundamental structural characteristics of glass will have a significant impact on the design and production of glass," said paper co-author Douglas Allan, a researcher at Corning Incorporated. "Our work shows that there is a clear correlation between the atomic ring structure of a glass and its glass transition temperature range, and therefore the performance characteristics of the glass."

Compiled source: ScitechDaily