Wear, Friction and NVH Characterization Using a Laboratory-Scale Tribometer

The current study presents some testing procedures which have been designed for friction and noise measurements of brake friction materials using a laboratory-scale tribometer. The uncertainties (errors) and precision of the measurements are also described in this paper. Some case studies related to friction, wear and noise related issues in brake friction materials were chosen to show the respective testing procedures. Through the error study, it was shown that the uncertainties of the lab. test bench are mainly associated with 3 variables: torque, force and sliding radius. The combined uncertainty of the friction measurements is less than or equal to ±1%, considering the typical operating range of the machine. The possibility of using two samples from a single brake pad also contributes to the reliability of the machine test and procedures. Finally, the laboratory-scale tribometer and testing procedures discussed in the present paper proved to be adequate to characterize friction, wear and Noise, Vibration and Harshness (NVH) related issues in brake friction materials.