In this study, the stability of sandwich conical shells covered by functionally graded and uniform distributed carbon nanotube-reinforced composite coatings under external pressures is carried out. The mechanical properties of the carbon nanotube and matrix are assumed to be graded through the thickness of the coatings via three types of grading rule. The basic relationships and stability equations of sandwich conical shells reinforced by carbon nanotubes are obtained employing the modified Donnell-type shell theory and generalized first-order shear deformation theory. The Galerkin procedure is employed to define expressions for the external buckling pressures. For the accuracy of the proposed formulation, the results are compared with the results that are published in the literature. It follows a systematic study aimed at checking the sensitivity of the structural response to the type of pattern and the volume fraction of carbon nanotubes in the composite coatings.

中文翻译：

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碳纳米管增强涂层复合锥形壳在外压下的稳定性

在这项研究中，进行了功能梯度和均匀分布的碳纳米管增强复合涂层覆盖的夹心锥壳在外部压力下的稳定性。假定碳纳米管和基体的机械性能通过三种类型的分级规则通过涂层的厚度分级。利用修正的Donnell型壳理论和广义一阶剪切变形理论，得到了碳纳米管增强夹心锥壳的基本关系和稳定性方程。Galerkin 程序用于定义外部屈曲压力的表达式。对于所提出的公式的准确性，将结果与文献中发表的结果进行比较。