To transform melts into glasses, the molten sample must be quenched – in other words, the material needs to be cooled rapidly in order to preserve its amorphous structure. This process plays an important role in geological phenomena like the solidification of magma, and a high-quench mechanism is necessary for studying these systems. Bondar et al. developed a multi-anvil technique that provides rapid cooling of a sample an order of magnitude faster than traditional multi-anvil experiments.
The setup consists of a traditional multi-anvil press with six steel anvils placed along four blocks, each of which is backed by an external press and transfers compression to the cubic volume bound by the anvils in the center. The apparatus is combined with a newly designed cell assembly and an optional external cooling system that maximizes heat flow out of the system.
According to the authors, the technique can supply cooling rates as high as 7,000 C/second – a large increase to the 130-650 C/second cooling rates by conventional assemblies. Even without the external cooling system, they observed rates up to 5,350 C/second. The technique allows for the quenching of various melts that conventional techniques cannot achieve, for example, to study silicate melts in glass form at room temperature using straightforward and adaptable analytical methods.
“This allows us, for example, to measure water and carbon dioxide partitioning between minerals and melts, which then may provide us with information on their content and distribution in Earth’s mantle,” said author Dmitry Bondar. Because this process has implications on water and carbon cycles in the Earth’s interior, these studies can be essential tools for geologists.
Source: “A rapid-quench technique for multi-anvil high-pressure-temperature experiments,” by Dmitry Bondar, Hongzhan Fei, Anthony C. Withers, and Tomoo Katsura, Review of Scientific Instruments (2020). The article can be accessed at https://doi.org/10.1063/5.0005936.
