Ceramic materials are generally more wear-resistant than metals. This is due to their inherent hardness and brittleness, which allows them to withstand abrasive forces better than metals. According to a study by the National Institute of Standards and Technology (NIST), ceramics can have hardness values up to 20 GPa, whereas the highest hardness for most metals is around 5 GPa. This significant difference in hardness contributes to the superior wear resistance of ceramics. Additionally, ceramics have a lower coefficient of friction, which reduces the wear rate when in contact with other materials. For instance, alumina ceramics, a common type of ceramic, can have a coefficient of friction as low as 0.2, compared to metals which typically range from 0.3 to 0.6. This lower friction further enhances the longevity of ceramic components in wear-resistant applications.