FRICTION COEFFICIENT VARIATION AT MINUTE VIBRATING VELOCITY BETWEEN BRAKE PAD AND DISC ROTOR

摘要

Research and/or Engineering Questions/Objective: Several mechanisms are assumed to cause brake squeal. The dμ/dv<0 theory is one of them. dμ/dv represents the slope of friction coefficient for sliding velocity. If dμ/dv is negative, disc vibrations may increase due to negative damping. It has been said for a long time that negative dμ/dv affects brake squeal. Many researchers measured dμ/dv to clarify squealing factors. In those results, the slope of friction coefficient at a steady sliding speed was used for dμ/dv. However, the pad undergoes minute vibrations during brake squealing. So, we thought that dμ/dv should be measured under vibrations.