The effect of steel fiber orientation on frictional properties of asbestos-free friction materials

The frictional properties of the composites reinforced with continuous steel fibers have been evaluated in LNBR modified phenolic resin based friction materials. The fiber orientations are introduced regarding the sliding direction, i.e. parallel (P) along the fiber direction, normal (N) and antiparallel (AP). The specific wear rates are increased if the sliding path is shifted from the P to the AP and N direction. The coefficient of friction is also dependent on the fiber alignment directions. The coefficients of these materials fall in the range of 0.49 to 0.54. The initial sliding interaction is plowing action if the turnplate temperature is below 250degreesC. Meanwhile, with the increase of the temperature, as ironed transfer film developed on the specimen, the interaction became adhesive and steady-state friction is established. The wear resistance of the composite is found to relate to the stability of the film.