BRIDGMAN ANVIL WITH A SINTERED DIAMOND CORE FOR PHASE-TRANSFORMATION STUDIES AT HIGH-PRESSURES AND HIGH-TEMPERATURES

A new Bridgman anvil composed of tungsten carbide with a sintered diamond core is described. The truncated face of the anvil is 26 mm in diameter, the central part of which consists of the sintered diamond core 15 mm in diameter. Using the newly developed Bridgman anvils, pressures up to about 20.5 GPa were successfully generated at room temperature. Phase transformation experiments were carried out using the Bridgman anvils with an internal heating system. 5-10 mg sample was charged in a single high-pressure high-temperature run. The disproportionation boundary of Zn2SiO4 modified spinel to a mixture of ZnSiO3 ilmenite and ZnO rocksalt was determined as P(GPa) = 12.3 + 1.3 x 10(-3)T(degrees-C) by the Bridgman anvil apparatus.