首页 | 本学科首页   官方微博 | 高级检索  
     检索      


The hydrostatic pressure derivatives of the elastic constants of indium and an indium cadmium alloy
Authors:SC Flower  GA Saunders  YK Yo?urtçu
Institution:School of Physics, University of Bath, Claverton Down, Bath BA2 7AY, U.K.;Atatürk University, Faculty of Science, Department of Physics, Erzurum, Turkey
Abstract:The hydrostatic pressure derivatives of the elastic stiffness constants of indium and indium-3.4 at.% cadmium alloy single crystals have been obtained from pulse echo overlap measurements of the dependence of ultrasonic wave velocities upon pressure. The softest zone centre acoustic phonon mode in indium is a shear mode propagating k along the 101] direction rather than that (k110], e11?0]) which drives the ferroelastic phase transition in the indium-cadmium alloys. The derivative δ((C11C12)/2)/δP is positive, accounting for the stability of the fct structure of indium under high pressure. Using the quasiharmonic, anisotropic continuum model the acoustic mode Grüneisen parameters have been calculated and are discussed in terms of mode softening. The high temperature limiting value$?γH (= 2.56) of the mean acoustic mode Grüneisen parameter is found to be close to the thermodynamic Grüneisen parameter γth (=2.5).
Keywords:
本文献已被 ScienceDirect 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号