Mechanical damping strongly influences the sensitivity and resolution of nano-sensors and actuators. In this paper, we have investigated one of the key intrinsic mechanisms responsible for dissipation of vibrational energy in beams composed of a polycrystalline material, namely motion of grain boundaries. The focus has been on modeling the movement of the grain boundary perpendicular to the interfacial plane. To this end, we have modeled the interface as an array of dislocations. By accounting for all forces acting on individual dislocations, we are able to extract the effective motion of the interface and thus compute cyclical energy losses. We have predicted the dependence of the mechanical quality factor (Q) on the grain boundary misorientation and inclination angles, and proposed an experiment based on our results.
Journal: TechConnect Briefs
Volume: 1, Technical Proceedings of the 2003 Nanotechnology Conference and Trade Show, Volume 1
Published: February 23, 2003
Pages: 364 - 367
Industry sectors: Advanced Materials & Manufacturing | Sensors, MEMS, Electronics
Topic: MEMS & NEMS Devices, Modeling & Applications