The objectives of this paper are to measure the dynamic modulus, its dependence on pre-load, spatial uniformity and temperature dependence for various friction material formulations and platforms. These baseline test results are compared with conventional compressibility test data. A total of 56 pads, five different formulations and six different platforms, are analyzed prior to performance testing. A subset of these pads is then subjected to various performance tests. The performance tests include J2521 as well as more aggressive, TI1160 and DM890 protocols. The characteristics of the same pads are then re-measured to quantify the irreversible changes in modulus as the result of performance testing. The magnitude of the variation in dynamic modulus, pad spatial uniformity, and pre-load dependence as the result of performance tests is quantified.

Redar, Martin, Hoxie, Steven, BWI Group, USA; Yuhas, Donald E., Vorres, Carol L., and Remiasz, Jacek, Industrial Measurement Systems Inc., USA