Pressure-induced disappearance of the gamma 2 (HgSn7-8) phase in dental amalgam.

Abstract

Examination of the crystalline structure of dental amalgam during an investigation that involved high pressures led to the detection of the disappearance of the γ2 phase after high pressure treatment. This phase disappearance was detected during periodic X-ray diffraction measurements made several months to a year after the samples had been subjected to pressures of up to 50 kilobars (750,000 psi) by use of a solid medium pressure apparatus. No new phases were detected during the process.