Size effects on the vibro-acoustic characteristics of different types of functionally graded sandwich microplates

Abstract

Due to the dynamic and acoustic characteristics of functionally graded microplates in micro- and nano-electro-mechanical systems, this paper established the vibro-acoustic governing equation of functionally graded (FG) sandwich microplates, which contains one material length scale parameter. Two types of FG sandwich microplates are studied, and the effects of different parameters on the vibro-acoustic characteristics are discussed. The results show that the size effect is significant when the thickness of microplate is close to the material length scale, especially at the higher order mode and for the thicker plate. Moreover, the sound insulation performance with the size effect increasing becomes better.

Keywords:

• Size effects
• vibration
• sound transmission loss
• modified couple stress theory
• functionally graded sandwich microplate

Acknowledgments

The authors gratefully acknowledge the Beijing Natural Science Foundation (No.1222006) and the support from the Natural Science Foundation of China (Grant Nos.11732005, 12172339).

Declaration of competing interest

The authors declare that they have no competing interests and do not have any conflict of interests regarding the publication of this manuscript.