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A brake durability experimental method is proposed to simulate a brake durability vehicle road test. Brake judder and noise often occur in brake durability road testing. Brake judder is difficult to address because of its many potential causes, such as assembly run out, component stiffness, lining characteristics, thermal coning/hot spot/thermal instability and corrosion. There are currently several test procedures to predict brake thermal roughness and pad cleaning corrosion performance for preventing brake judder. Brake durability vehicle road testing is performed to check brake NVH and wear; examples include the Mojacar test in Spain and the Huangshan test in China. Brake energy intensity and road vibration are the significant factors that cause brake rotor thickness variation, which generates brake judder in public road testing.

The performance of brake system is dependent on the interaction between brake pad and rotor at the friction interface. The mechanical properties of the brake rotor that is made of gray cast iron are directly influenced by composition and microstructure. The elasticity modulus and the damping capacity play a significant role on the propensity of the brake rotor to generate noise. Brake squeal propensity was studied by investigating the correlation between the microstructure of gray iron brake rotor and the carbon equivalent (CE). The gray iron samples were manufactured to have different microstructures by changing the carbon equivalent (C.E.). The squeal noise tests were performed with different C.E rotors. The test results show potential of the high carbon composite rotor material to reduce the squeal noise propensity. In order to understand the effect of rotor microstructure and composition on squeal, resonant frequencies and damping ratios were evaluated.