SAE J 2968/1:2022-09-30

This SAE Recommended Practice is intended as the definition of a standard test, which may be subject to frequent change to keep pace with experience and technical advances. This should be kept in mind when considering its use. The specific purpose of this SAE Recommended Practice is to define a procedure to determine intrinsic properties of friction materials such as compressive modulus and rebound/recovery time at specific fatigue test pressures. Results from this test will both independently characterize the friction material and serve as input to the compression fatigue test. NOTE: If this test is intended to determine the rebound interval for the compression fatigue test, then the maximum test pressure (Pmax) in this procedure must be selected with future fatigue testing levels in mind. It is important that the rebound time is sufficient at the maximum apply pressure to allow the matieral to rebound back to its original thickness. Standard reporting processes are recommended. This procedure is intended for use by both suppliers and end users of wet friction materials. The only variables selected by the supplier or user of the friction system are: a Friction material. b Fluid. c Maximum load. d Fatigue test cycle requirements. These variables must be clearly identified when reporting the results of this test. Data shall not be reported as having been obtained using this procedure if any test parameters or system hardware described in this document are changed or deviated from in any way (other than the variables described above).