Improvement of mechanical and wear behaviour of fiber-reinforced polypropylene composites for the rail industry

There is a growing need for advanced composite materials due to increasing areas of applications that are unachievable by single materials. Material surfaces are prone to wear due to contact with other materials, applied load and the nature of the material itself, thus the need for improved composite materials. The influence of applied load on the wear behaviour of polymeric-based composites, produced with several fillers and fibers as reinforcements, is reported in studies. The reinforcing fiber was alkaline treated (5 wt% NaOH) for improved strength and interfacial adhesion between the polymer matrix and the fiber. The reinforced composites were developed by extrusion, followed by compressive molding. The wear analysis was done by varying the applied load (5, 10, and 20 N). Based on the findings of this study, there was an increase of between 51 and 79 % in the wear rate as the applied load increased from 5 to 20 N due to a higher coefficient of friction with increasing load. Increasing fiber loading from 10 to 40 wt% led to a decrease of 75, 38 and 36 % in the wear rate of the reinforced composites for applied load of 5, 10 and 20 N, respectively. The impact strength and water absorption rate were observed to have increased with increasing fiber contents. The study shows that reinforced polypropylene composites recorded improved wear resistance, which means that the properties of reinforced composites largely depend on the fiber content, interfacial bonding between the polymer matrix and the reinforcing fibers and applied load. This makes the composite material ideal for the transport industry.