principal strain [力] 主应变 ; 枝变 ; 主形变
major principal strain 最大主应变
principal strain ratio 枝变比 ; 主应变比
principal strain direction 枝变方向
maximum principal strain 最大主应变
principal axes of strain 形变主轴 ; 主应变轴
principal shear strain [力] 主剪应变
An equation for the calculation of true shear strain was derived from the integration of infinitesimal shear strain in plane shearing process with constant principal shear strain direction.
对切应变主轴不变的平面简单切变过程，通过无穷小应变的积分，导出了真实切应变计算公式。
Only if this short crack extends long enough and blunted wide enough, can it affect the principal crack extension and the distribution of stress and plastic strain.
只有小裂纹扩展到足够长并钝化到足够宽，才能够影响主裂纹的扩展及其前端应力、应变的分布。
Then the principal strain measurement and forming safety margin prediction in defect regions are conducted.
接着对缺陷区域进行主应变测量和安全成形裕度预测。
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