On the 100 nanometer scale, amorphous minerals reveal their true nature

Deformation of minerals, an ancient subject of study for mineralogists, has always received great interest. While the process is well understood for conventional metals, amorphous metals, such as metallic glasses, remain a mystery, especially at the nanoscale. A new study provides new insights into this topic.

Amorphous minerals, or Metal glassesThey are materials that combine the strength of metals and the formability of plastic. They are being developed for a wide range of applications, from aerospace to consumer electronics, robotics and biotechnology.

Their unique atomic structure gives them these properties: When they transform from liquid to solid, their atoms arrange themselves randomly and do not crystallize as traditional metals do. However, preventing atoms from crystallizing is a challenge, and any knowledge about how they work could dramatically improve the production of metallic glasses.

As the study authors point out, “ To advance the fabrication and use of amorphous metals, a fundamental and complete understanding of their deformation as a function of size and temperature is necessary “.

Laboratory of Professor Jan SchroersYale University I decided to study what happens when nanometer-sized samples of amorphous minerals deform. Using copper, zirconium, and other metallic glass samples in a soft state, they found that the standard rules began to diverge for sample sizes of 100 nanometers or less.

At this scale, the chemical composition of the samples would never change if the atoms continued to move en masse. Instead, the atoms moved individually, and at a certain point, the metal began to deform rapidly.

” If you reduce the volume more and more, the atoms will no longer flow. What they do instead is move individually across the surface “, commented Jan Schruers.

Scientific and technological implications

These discoveries have major implications at both the scientific and technological levels. It provides a new method for slowly growing unstable materials, including metallic glasses and even other materials that could not be made using other techniques.

Jan Schruers' laboratory is currently focusing on the most promising alloys for making metallic glasses in this way. ” The alloy must contain elements that are similar, but not too similar, otherwise the pattern on which it grows cannot be transformed into glass. », concluded the professor.

Synthetic

Deformation of amorphous metals, a complex and poorly understood topic, has been highlighted by a new study. These findings could have major implications for the production of metallic glasses and other metastable materials, paving the way for new applications in various fields.

For better understanding

What is an amorphous mineral?

Amorphous metal, or metallic glass, is a material that combines the strength of metals with the malleability of plastic. It does not crystallize as traditional metals do when they change from a liquid to a solid state.

What makes it difficult to understand the deformation of amorphous metals?

The complexity lies in the fact that the atoms of these metals arrange themselves randomly and do not crystallize. In addition, at the nanoscale, standard rules of deformation do not apply.

What did the Schruers study find?

The study found that nanometer-sized atoms of the amorphous metal move individually during deformation, unlike what happens on a larger scale.

What are the implications of these findings?

These discoveries could improve the production of metallic glasses and other metastable materials, and pave the way for new applications in various fields.

What are the application areas of amorphous metals?

Amorphous metals are being developed for a wide range of applications, from aerospace and consumer electronics to robotics and biotechnology.

References

Article: “Size-dependent deformation behavior in nanoscale amorphous metals indicating a transition from collective to single atomic transport” – DOI: s41467-023-41582-2

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