Influence of Distributed Stiffness in Contact Surface on Disk Brake Squeal

This research examined the squeal generation mechanism of a disk brake focusing on the stiffness of the frictional contact surface between the disk and the pad (contact stiffness). To clarify the influence of the contact stiffness, an experimental apparatus with a simple structure was used for squeal tests instead of an actual disk brake, and the dynamic stiffness of the contact surface was measured. In addition, a surface-contact model that includes the frictional contact surface composed of the distributed spring and three degrees of freedom was made. The results show that the pressure dependency of the contact stiffness is the cause of squealing.