当前位置: X-MOL 学术Arch. Civ. Mech. Eng. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Free vibration and buckling analyses of FG porous sandwich curved microbeams in thermal environment under magnetic field based on modified couple stress theory
Archives of Civil and Mechanical Engineering ( IF 4.4 ) Pub Date : 2021-01-02 , DOI: 10.1007/s43452-020-00150-x
Ehsan Arshid , Hossein Arshid , Saeed Amir , S. Behnam Mousavi

Porous sandwich structures include different numbers of layers and are capable of demonstrating higher values of strength to weight ratio in comparison with traditional sandwich structures. Free vibration and mechanical buckling responses of a three-layered curved microbeam was investigated under the Lorentz magnetic load in the current study. A viscoelastic substrate was considered and the effect of the thermal environment on its mechanical properties was assessed. The core was composed of the functionally graded porous materials whose properties changed across the thickness based on some given functions. The face sheets were FG-carbon nanotube-reinforced composites and the influence of the placement of CNTs was evaluated on the behavior of the faces. Using the extended rule of mixture, their effective properties were determined. Modified couple stress theory was used to predict the results in the micro-dimension. While the governing equations were derived based on the higher order shear deformation theory and energy method, and mathematically solved via Navier’s method. The results were validated with the previously published works, considering the effects of various parameters. As comprehensively explained in the results section, natural frequencies and critical buckling loads were reduced by enhancing the central opening angle. Moreover, an increase in the porosity coefficient declined the mentioned values, but increasing the CNTs content showed the opposite effect. The outcomes of this study may help in the design and manufacturing of various equipment using such smart structures, making high stiffness to weight ratios more accessible.



中文翻译:

基于修正耦合应力理论的FG多孔夹层弯曲微梁在热环境下的自由振动和屈曲分析

多孔夹心结构包括不同数量的层,并且与传统夹心结构相比,能够显示出更高的强度重量比值。在当前研究中,研究了三层弯曲微梁在Lorentz磁载荷下的自由振动和机械屈曲响应。考虑了粘弹性基材,并评估了热环境对其机械性能的影响。纤芯由功能梯度的多孔材料组成,其性能根据某些给定的功能在整个厚度范围内变化。面板是FG-碳纳米管增强的复合材料,并评估了CNT的放置对表面行为的影响。使用扩展的混合规则,确定了它们的有效性质。改进的耦合应力理论用于预测微观尺寸的结果。而控制方程是根据高阶剪切变形理论和能量方法推导的,并通过Navier方法数学求解。考虑到各种参数的影响,结果已通过以前发表的工作进行了验证。正如结果部分中全面解释的那样,通过增加中心打开角度可以减少固有频率和临界屈曲载荷。此外,孔隙率系数的增加降低了所述值,但是增加CNT的含量显示出相反的效果。这项研究的结果可能有助于使用此类智能结构设计和制造各种设备,从而使高刚度重量比更容易获得。

更新日期:2021-01-02
down
wechat
bug