Tribological and physio-mechanical characterization of cow dung fibers reinforced friction composites: An effective utilization of cow dung waste

The present work was an attempt to use cow dung fibers as reinforcing components in friction composites. Two groups of the samples based on cow dung fibers and corn stalk fibers were fabricated by heat-press molding method. The tribological and physio-mechanical properties of the fabricated samples were evaluated and the worn surface morphologies were analyzed by means of scanning electron microscope (SEM) and confocal laser scanning microscope (CLSM). This work revealed that the positive effect of cow dung fibers on the friction and wear properties of friction composites. Moreover, the friction composites reinforced by cow dung fibers had more stable friction coefficients and more pronounced wear resistance than those reinforced by corn stalk fibers. Taking into account the overall performance, the sample containing 6 wt% cow dung fibers (sample FCD-6) was selected as the best performing, with the fade ratio of 6.9%, recovery ratio of 107.7% and sum wear rate of 1.616 × 10−7 cm3 N−1 m−1. Furthermore, the SEM and CLSM results revealed that the worn surface of sample FCD-6 exhibited superior fiber-matrix interfacial adhesion and more stable secondary contact plateaus, which were responsible for the best wear resistance performance. The work was a valuable contribution for the environmentally friendly utilization of cow dung waste in automotive braking applications.