Effect of Brake Plate and Fin Joint on Rotor Noise Damping

Hayes Lemmerz, in a previous paper (Ref-1), has introduced an HQ (Hayes Quiet) rotor design where the noise level was reduced by 50%. In this paper, various methods of joining the brake plates to the fins are investigated. The effect of welding is to create a metal joining path which connects the bell shape of the rotor and consequently, the noise level increases. Glue between the brake plates and fins acts as an excellent noise damping layer, but welding through such a layer introduces porosity. The successful design used in the HQ Rotor is when brake plates and long fins are glued together and in place of short fins flat head screws that are used to hold the brake plates against the fin's surfaces. The result of this joint is a Q-Factor number of 211. Damped iron cast joints exhibits a Q-Factor of 500. Glued joints with screws show a Q-Factor of 211 and this kind of joint does not raise the Q-Factor compared to just glued joints. Hayes Lemmerz is currently testing this HQ rotor on Dynamometer and Vehicle tests.