Sapphire-Anvil Cell for High Pressure Research

Abstract
A pair of sapphire crystals was used for opposed anvils of a high pressure cell. Various types of anvils were attempted. The shapes of all anvils were fundamentally a truncated rod but they differed in minor designs. Maximum pressures of about 14 GPa was attained by the use of anvils with top and bottom surfaces respectively 1 and 5 mm in diameter and with an angle of 18° between the top surface and tapered flank. No particular relation, which is expected to favor the generation of high pressure, was found between the crystallographic axes and the direction of compression.