Abstract

The present study analyzes effective elastic properties of two-layered composite tubes from seven-constant tetragonal crystals under tension. Analytical dependencies of Young’s modulus and Poisson’s ratios on elastic properties and geometric parameters of the tube are obtained. Values of these elastic characteristics compared to the values of Voigt’s averages for Young’s moduli of rectilinearly-anisotropic crystals and single-layered tubes of corresponding thickness. Auxetic two-layered tubes determined. It is shown that two-layered tubes of seven-constant tetragonal crystals are characterized by linear Poynting’s effect – the longitudinal strain is proportional to the torque angle.

中文翻译：

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七常数四方晶体两层管的弹性性能

摘要

本研究分析了七常数四方晶体双层复合管在拉伸下的有效弹性性能。获得了杨氏模量和泊松比对管的弹性特性和几何参数的分析依赖性。这些弹性特性的值与直线各向异性晶体和相应厚度的单层管的杨氏模量的福伊特平均值相比。确定拉胀两层管。结果表明，七常数四方晶体的两层管具有线性坡印廷效应——纵向应变与扭矩角成正比。