High-temperature elastic constants of yttrium aluminum garnet

Abstract

Elastic constants of yttrium aluminum garnet have been measured in the temperature range 300–1450 K using a combination of Brillouin scattering and refractive index measurements. Associated quantities such as the bulk modulus, anisotropy ratio, and thermo-optic coefficient have been determined.

Comparison of the Mechanical Properties of Single Crystal and Polycrystalline Yttrium Aluminum Garnet

“…The single crystal was assumed to be elastically isotropic in order to calculate approximate values of bulk modulus and Poisson's ratio. This is a reasonable approximation as the anisotropy factor for the single crystal is close to unity 3 . The two sets of elastic constants for the single and polycrystalline YAG are very similar.…”

“…The single crystal elastic constants of YAG have been measured previously with excellent agreement 3–5 . The elastic constants of polycrystalline YAG have also been reported 6 .…”

Elasticity and lattice vibrational properties of transparent polycrystalline yttrium–aluminium garnet: Experiments and pair potential calculations

“…Previous Brillouin light scattering (BLS) or acoustic studies dealt with single crystal and measurements of high temperature or pressure dependant elastic properties associated with refractive index measurements. [11][12][13][14] In this paper, the elastic, the dielectric and vibration properties of polycrystalline samples are studied in relation with the crystallographic texture. The experimental investigations have been carried out using X-ray diffraction, Raman scattering, infrared-visible reflectometry with oblique incidence and the BLS technique which has proved to be a powerful nondestructive tool for the elastic characterization of layered structures and bulk materials.…”

Compact high-temperature cell for Brillouin scattering measurements

“…Other limitations may include ͑1͒ difficulty in the precise orientation of samples, ͑2͒ very limited angular access to the sample, which restricts the number of scattering directions and elastic constants that can be obtained, especially for symmetries lower than cubic, and ͑3͒ difficulty in measuring the refractive index as a function of temperature independently. 8,10 To overcome these problems we designed a ceramic high-temperature cell for single-crystal Brillouin spectroscopy to temperatures in excess of 1000°C. The cell is compact ͑about 5 cm in the maximum dimension͒, and easily fits onto any standard three-or four-circle goniometer, allowing a number of additional applications such as x-ray scattering, etc.…”