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Strength of solid helium under high pressure

IR@NAL: CSIR-National Aerospace Laboratories, Bangalore


Field	Value

Title	Strength of solid helium under high pressure

Creator	Singh, AK

Subject	Chemistry and Materials (General)

Description	Helium is commonly used as a pressure transmitting medium to render the sample pressure hydrostatic in high pressure experiments with diamond anvil cells. On solidification under pressure helium begins to develop strength that is characteristic of any solid. The estimation of the compressive strength of helium as a function of pressure is important as it helps in estimating the nonhydrostatic stresses that can develop in the sample even when it remains immersed in helium pressure transmitting medium. The x-ray diffraction data on polycrystalline samples obtained with the radial diffraction geometry are commonly used to determine the compressive strength of solids. This method fails in the case of helium because of its low scattering power. The nonhydrostatic stresses that develop in crystalline solids immersed in helium pressure transmitting medium were used to estimate the strength of helium. The diffraction data available in the literature were selected for this study. It was important for this study to consider the data from the experiments that were conducted ensuring that the samples did not come in contact with the anvils. The analysis of these data suggests that the strength of helium remains low (< 0.1 GPa) at pressures below 20 GPa and increases to -2 GPa at 100 GPa.

Publisher	IOP Publishing Ltd

Type	Conference or Workshop Item PeerReviewed

Format	application/pdf

Identifier	http://nal-ir.nal.res.in/10833/1/He_strength_2012.pdf Singh, AK Strength of solid helium under high pressure. In: 23rd International Conference on High Pressure Science and Technology (AIRAPT-23): Journal of Physics: Conference Series 377 (2012) 012007, 25–30 September 2011, BARC, Mumbai.

Relation	http://nal-ir.nal.res.in/10833/