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

单轴向拉伸实验晶粒组构的变化
引用本文:李军,王伟利.单轴向拉伸实验晶粒组构的变化[J].极地研究,1992,4(1):29-35.
作者姓名:李军  王伟利
作者单位:中国科学院兰州冰川冻土研究所 兰州730000 (李军),中国科学院兰州冰川冻土研究所 兰州730000(王伟利)
摘    要:采用实验室制备的具有随机取向的细晶粒多晶冰 ,在温度为 - 3 .0± 0 .0 5℃、初始八面体剪应力为 0 .2 MPa和 0 .3 MPa下 ,对六个样品进行了单轴向拉伸实验。对应于八面体剪应力为0 .2 MPa的一次实验 ,最小应变率为 2 .6× 1 0 - 8s- 1;对应于八面体剪应力为 0 .3 MPa的其余五次实验 ,最小应变率平均值为 8.6× 1 0 - 8s- 1。六次实验最小应变率均出现在总八面体剪应变为1 .1~ 1 .6 %之间。晶粒 c轴组构随总应变增大向大环型发展 ,最终形成以组构平均半角趋于稳定在 6 5度左右的大环型组构 ,但在总八面体剪应变达 2 0 %之前 ,可能受组构图本身几何性质影响 ,组构平均半角随应变增加反而减小。对比压缩实验结果 ,拉伸实验最小应变率值与同等条件下压缩实验得到的最小应变率值一致 ,但最小应变率出现时对应的总应变稍大 ,c轴组构转变所需的总应变则更大。

关 键 词:总八面体剪应变  最小应变率  晶粒c轴组构  组构平均半角

CHANGES OF CRYSTAL C-AXIS ORIENTATION FABRIC IN UNIAXIAL EXTENSION TESTS
Li Jun,Wang Weili.CHANGES OF CRYSTAL C-AXIS ORIENTATION FABRIC IN UNIAXIAL EXTENSION TESTS[J].Chinese Journal of Polar Research,1992,4(1):29-35.
Authors:Li Jun  Wang Weili
Abstract:Uniaxial extension tests were performed until large amount of strain on six laboratory-prepared ice samples with initial randomly-oriented fine crystals at the temperature -3.0±0.05C° and the octahedral shear stress 0.2MPa and 0.3MPa. The minimum octahedral shear strain rate is 2.6x10 -8 s -1 for one test at octahedral shear stress 0.2MPa and the average 8.6x10 -8 s -1 for the other five at octahedral shear stress 0.3MPa and occurred at the total octahedral shear strain between 1% and 1.6% in all tests. With the increasing strain, the crystal c-axis orientation changes developing a large girdle fabric with mean half girdle angle around 65° at total octahedral shear strain approximately 60%. Beyond this, the mean half girdle angle tends to be steady. However, possibly due to the geometry of fabric diagram the mean half girdle angle deceases before 20% or so total octahedral shear strain. In comparison with the results from uniaxial compression tests, the minimum strain rate in extension agrees to that in compression at same temperature and stress, but the total strain is slightly greater at the minimum strain rate and much greater to develop the fabric.
Keywords:total octahedral shear strain  minimum strain rate  crystal c-axis orientation fabric  mean half girdle angle  
本文献已被 CNKI 等数据库收录!
点击此处可从《极地研究》浏览原始摘要信息
点击此处可从《极地研究》下载免费的PDF全文
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