Jiang Jize, Tang Feixiang, He Siyu, Dong Fang, Liu Sheng
Key Laboratory of Transients in Hydraulic Machinery, Ministry of Education, School of Power and Mechanical Engineering, Wuhan University, Wuhan 430072, China.
China-EU Insititute for Clean and Renewable Energy, Huazhong University of Science & Technology, Wuhan 430074, China.
Nanomaterials (Basel). 2024 Jul 3;14(13):1144. doi: 10.3390/nano14131144.
The vibrations in functionally graded porous Cu-Si microcantilever beams are investigated based on physical neutral plane theory, modified coupled stress theory, and scale distribution theory (MCST&SDT). Porous microcantilever beams define four pore distributions. Considering the physical neutral plane theory, the material properties of the beams are computed through four different power-law distributions. The material properties of microcantilever beams are corrected by scale effects based on modified coupled stress theory. Considering the fluid driving force, the amplitude-frequency response spectra and resonant frequencies of the porous microcantilever beam in three different fluids are obtained based on the Euler-Bernoulli beam theory. The quality factors of porous microcantilever beams in three different fluids are derived by estimating the equation. The computational analysis shows that the presence of pores in microcantilever beams leads to a decrease in Young's modulus. Different pore distributions affect the material properties to different degrees. The gain effect of the scale effect is weakened, but the one-dimensional temperature field and amplitude-frequency response spectra show an increasing trend. The quality factor is decreased by porosity, and the degree of influence of porosity increases as the beam thickness increases. The gradient factor n has a greater effect on the resonant frequency. The effect of porosity on the resonant frequency is negatively correlated when the gradient factor is small (n<1) but positively correlated when the gradient factor is large (n>1).
基于物理中性面理论、修正耦合应力理论和尺度分布理论（MCST&SDT），对功能梯度多孔铜硅微悬臂梁的振动进行了研究。多孔微悬臂梁定义了四种孔隙分布。考虑物理中性面理论，通过四种不同的幂律分布计算梁的材料特性。基于修正耦合应力理论，考虑尺度效应修正微悬臂梁的材料特性。考虑流体驱动力，基于欧拉-伯努利梁理论获得了多孔微悬臂梁在三种不同流体中的幅频响应谱和共振频率。通过估计方程推导了多孔微悬臂梁在三种不同流体中的品质因数。计算分析表明，微悬臂梁中孔隙的存在导致杨氏模量降低。不同的孔隙分布对材料特性的影响程度不同。尺度效应的增益效应减弱，但一维温度场和幅频响应谱呈上升趋势。品质因数随孔隙率降低，且孔隙率的影响程度随梁厚度增加而增大。梯度因子n对共振频率有较大影响。当梯度因子较小时（n<1），孔隙率对共振频率的影响呈负相关；而当梯度因子较大时（n>1），孔隙率对共振频率的影响呈正相关。
