The physical meaning of Cosserat, void, and microstretch elastic constants is analyzed and interpreted. Various torsion experiment designs provide a clear path to extract Cosserat elastic constants independently of any dilatation gradient sensitivity the material may have. For void elasticity (with sensitivity to dilatation gradients) there is no known quasi-static modality to demonstrate phenomena or extract elastic constants independently of any sensitivity to rotation gradients. Wave methods may be appropriate if there is minimal viscoelastic dispersion. Microstretch elasticity, which includes sensitivity to gradients of rotation and of dilatation could account for bending effects larger than those of Cosserat elasticity.

中文翻译：

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Cosserat、空隙和微拉伸弹性中弹性常数的物理意义

分析和解释了 Cosserat、空隙和微拉伸弹性常数的物理意义。各种扭转实验设计为独立于材料可能具有的任何膨胀梯度敏感性而提取 Cosserat 弹性常数提供了清晰的途径。对于空隙弹性（对膨胀梯度敏感），没有已知的准静态模态可以独立于对旋转梯度的任何敏感性来证明现象或提取弹性常数。如果粘弹性分散最小，波浪法可能是合适的。微拉伸弹性，包括对旋转梯度和膨胀的敏感性，可以解释比 Cosserat 弹性更大的弯曲效应。