Mechanical Properties of Cost-Effective Polypropylene Composites Filled with Red-Mud Particles

In recent years, the use of filler materials, such as red mud, in composites has increased. In this study, the use of industrial waste red mud as a filler material in an isotactic polypropylene (iPP) polymer–matrix composite (PMC) was investigated. A variety of mechanical tests were performed on the unreinforced polymer and on composites with 10, 20, 30, 40 and 50 wt.% red mud. Tensile strength, three-point flexural strength and hardness tests have been carried out, and the relationships between the red-mud content and properties were examined. Scanning electron microscopy (SEM) was applied to the fractured surfaces after three-point flexural tests. The results showed that, while the values of tensile and flexural strength were decreased, the hardness was increased with increasing red-mud content.