Abstract: In response to the issue of brake squeal noise in a certain automotive disc brake,brake pads with different chamfer structures,shim with different damping layer thicknesses,and the impact of their matching on brake squeal noise were studied.The optimal matching scheme and the original scheme obtained from the research were tested for noise through bench tests.The research results show that among the five types of brake pad chamfer structures,the symmetrical straight chamfer has the best noise reduction effect,and the chamfer of the symmetrical structure is better than the asymmetric structure. The chamfer of the asymmetric structure has a better effect on solving single noise with concentrated frequency,but it is easy to induce new noise;when the thickness of the damping layer of the shim gradually increases,the tendency of squeal noise occurrence shows a trend of first decreasing and then increasing;the reasonable matching of brake pad and shim can effectively improve squealing noise. The noise reduction trend of brake pad with symmetrical chamfer and asymmetric chamfer structures when matched with shim is opposite. Among them,the brake pad with symmetrical oblique chamfer structure has the best noise reduction effect when matched with shim with a damping layer thickness of 0.28 mm,and the noise occurrence rate is reduced by 97.98 % compared to the original plan.

Key words: squeal noise, brake pad, shim, disc brake