微粒对多晶冰流变行为的影响——(Ⅱ)滞弹性行为  

Effect of fine particles on the flow behavior ofpolycrystalline ice—(Ⅱ) anelastic behavior

作　　者：宋旼[1] David M Cole Ian Baker 

机构地区：[1]中南大学粉末冶金国家重点实验室 [2]US Army Cold Regions Research and Engineering Laboratory,Hanover,NH03755,USA [3]Thayer School of Engineering,Dartmouth College,Hanover,NH03755,USA

出　　处：《地球物理学报》2007年第4期1156-1160,共5页Chinese Journal of Geophysics

基　　金：美国国家科学基金(National Science Foundation)极地科学研究部(OPP011737)资助

摘　　要：用反相直接加载的方法研究了微粒对多晶冰滞弹性的影响.结果表明:在较高频率时(1Hz和10-1Hz),滞弹性应变与应力峰值呈线性关系;在较低频率时(10-2Hz),其应力/应变偏离线性关系.微粒在高频时(1Hz)通过阻碍晶界滑移对晶界弛豫产生重要影响,增加了模量和降低了内耗.但微粒对低频时的位错弛豫没有明显的影响.通过滞弹性实验计算了非线性弛豫模型的两个重要参数,计算表明K值约为0.07Pa,α值约为0.54.Effects of particles on the anelasticity of polycrystalline ice have been studied by the inverse-direct loading method. The results indicated that at relatively higher frequencies （1 Hz and 10^-1 Hz）, anelastic strain has a linear relationship with the stress; and at relatively lower frequency （10^-2 Hz）, the stress/strain deviates from linear relationship. Particles have severe influence on the grain boundary relaxation through inhibiting grain boundary sliding at high frequency （1 Hz）, and thus increase the modulus and decrease the internal friction. However, particles have no obvious influence on the dislocation relaxation. Two important parameters have been calculated through the anelastic experiments. The results indicated that K value is - 0.07 Pa and α value is - 0.54.

关 键 词：冰与冰川 滞弹性 弛豫模型 流变 

分 类 号：P512[天文地球—地质学]