Locally induced chemical conversion processes — A means to control tribological properties of polymer composites?

Abstract Thermoplastics are gaining traction as materials for tribological systems. However, varying load conditions and unintentional temperature excursions make the behavior unpredictable and raise the need for smart materials able to react to changes in the systems boundary conditions. Utilizing fillers with physical or chemical material transformations, e.g. flame-retardants, seems to be a promising approach. In the present study, a polyamide based compound reinforced with carbon fibers and filled with the flame-retardant magnesium hydroxide was investigated. Tribological tests were performed on a Pin-on-Disk tribometer under constant sliding speed and incrementally increasing contact pressure. Compared to an unfilled reference, a significant improvement of the tribological performance could be demonstrated. Local hot spots in the contact interface trigger the material transformation which actively prevents severe thermal damage.