Nonlinear pressure dependence of the elastic moduli of fused quartz up to 3 GPa

摘要

The elastic moduli of fused quartz have been determined by ultrasonic measurements under high hydrostatic compressive stress and showed a nonlinear decrease to a minimum value at 2.1ndash;2.5 GPa, and thereafter an increase with increasing pressure. Changes in the Debye temperature and the Gruuml;neisen constant are determined using the present results. Assuming a contribution of the fourthhyphen;order elastic constants to the nonlinear dependence,C1111,C1112,C1122, andC1123have been tentatively evaluated to be 11.0plusmn;1.0, 10.8plusmn;3.6, 22.7plusmn;11.1, and 8.6plusmn;2.0 TPa, respectively. However, the possibilities of a complicated potential curve or a higherhyphen;order phase transition are also discussed.