Influence of surface integrity on vibration characteristics of microbeams

This is the first study on the influence of the surface integrity on the vibration characteristics of microbeams. A new model that represents the real surface texture of beams is developed. This model incorporates measures for the surface roughness, surface waviness, altered layer, and surface excess energy. This model outweighs Gurtin-Murdoch surface model by representing beams with real engineering surfaces. The derived model is solved for the free vibration of simple-supported, cantilever, and clamped-clamped microbeams. A parametric study is carried out to demonstrate the variations of the natural frequencies of microbeams due to surface integrity and a beam size decrease. It was revealed that a decrease in the beam size is accompanied with an increase in the surface integrity effects. Moreover, the surface integrity may decrease/increase the beam natural frequency. Surface integrity either softens the beam and hence decreases its natural frequency or inhibits the vibration propagation through the beam and hence increases the beam frequency.