PLASTIC DEFORMATION OF MgO SINGLE CRYSTALS UP TO 1600 C
PLASTIC DEFORMATION OF MgO SINGLE CRYSTALS UP TO 1600 C
复制标题
MgO 单晶在 1600 C 以下的塑性变形
DOI：
--
复制
发表时间：
1965
期刊：
影响因子：
--
通讯作者：
J. A. Pask
中科院分区：
文献类型：
--
作者：
S. Copley;J. A. Pask
本文给出了MgO单晶在1000° ~ 1600°C温度范围内沿（100）和（111）应力轴压缩的应力-应变曲线。在此温度范围内，（100）试样的屈服应力略有下降。应变硬化速率在约1100°C时达到最大值，在1600°C时降低约8倍。在约1100°C以上，（100）试样的应变速率对应力变化的敏感性大大降低，应力-应变曲线的形状发生变化。（111）试样的屈服应力随温度的升高而迅速下降，直到1600°C时，斜率不变。（111）和（100）试样的屈服应力之比在1200° ~ 1600°C范围内不断减小。使用各种应力速率来获得在1300°C下的应变硬化的量度。在1000° C和1400°C下进行静态恢复实验。在1000°C下，在卸载期间发生静态钉扎;在1400°C下发生正向恢复。根据晶体中位错线的长度和位错的平均运动速度，采用动力学方法对应力-应变曲线进行了分析。
Stress-strain curves are presented for MgO single crystals, compressed with (100) and (111) stress axes, for temperatures from 1000° to 1600°C. The yield stress of (100) specimens decreases slightly in this temperature range. The strain-hardening rate passes through a maximum at about 1100°C and decreases by a factor of about 8 at 1600°C. Above about 1100°C, the strain rate of (100) specimens is considerably less sensitive to changes in stress and the shape of the stress-strain curves changes. The yield stress of (111) specimens decreases rapidly with increasing temperature without a change of slope up to 1600°C. The ratio of the yield stresses for (111) and (100) specimens decreases continually from 1200° to 1600°C. Various stress rates were used to obtain a measure of strain hardening at 1300°C. Static recovery experiments were carried out at 1000° and 1400°C. At 1000°C static pinning occurred during the unloaded period; at 1400°C orthorecovery occurred. Stress-strain curves were analyzed by a dynamic approach based on the length of moving dislocation line in the crystal and the average dislocation velocity.