Toward a Better Understanding of...
Adaptation of a Ni:Cr:Al Alloy for Use in a Diamond Anvil Cell George Matthew Ferguson Mentor: James Schilling A nickel, chromium, aluminum material known as the Russian alloy (Ni:Cr:Al) is a non-superconducting alloy with a weak temperature-dependent magnetic response. The Russian alloy’s weak magnetic properties combined with its hardness after heat treatment make it a candidate for use in high pressure, low temperature experiments. The goal of this research was to adapt the alloy for use in a diamond anvil cell highpressure system as a gasket material. Such a gasket would allow measurements at lower temperatures than other common gasket materials. In order to be used in highpressure experiments, gaskets must be both hard and ductile. In order to study the mechanical properties of Ni:Cr:Al gaskets, I subjected samples of the material to various heat treatments and measured the hardness. After hardening I studied how the material deforms under pressure by placing the gaskets between two diamond anvils and applying pressure. Gaskets that show signs of cracking during this indentation process are likely too brittle and may crack through if used in a measurement. I found that many of the hardest Ni:Cr:Al gaskets cracked when subjected to pressure. Unfortunately, the gaskets that showed no signs of cracking were somewhat softer than other materials typically used for gaskets. Due to its favorable magnetic properties, however, the Russian alloy will likely still prove useful as a material either for gaskets or diamond anvil supports in a diamond anvil cell.
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