Circular sawblade vibration suppression by thermal stress stiffening method

In this paper, a temperature-controlled circular saw is proposed by a thermal stress stiffening method, which provides a novel approach that is easy to implement for suppressing sawblade’s vibration and improving machining quality. In this method, the sawblade’s inner boundary is heated by infrared radiation to generate in-plane thermal stress and improve the sawblade’s bending stiffness. Through theoretical calculation and experiment, it is found that increasing the inner boundary’s temperature can effectively increase the natural frequency of the sawblade’s dominant mode. Considering that the saw blade operates near and far from its resonant speed, four cutting experiments are performed on a same beech wood bar under temperature-controlled or uncontrolled conditions. The transverse vibration of the sawblade is measured by a laser displacement sensor, and the surface topography of the cut workpiece is obtained by a three-dimensional surface topography measuring device. This vibration suppression method significantly reduces the vibration amplitude of the sawblade, and effectively improves the machining quality of the circular saw. The experimental results show that using this method can reduce the defect depth of cutting processing by more than 60% when the sawblade rotates near its resonance speed, and is also effective when resonance does not occur.