Tribological Behavior and Thermal Stability of Thermoplastic Polyimide/Poly (Ether Ether Ketone) Blends at Elevated Temperature

In this study, a series of thermoplastic polyimide (TPI) reinforced poly (ether ether ketone) (PEEK) blends with varied TPI content were prepared by a hot-pressing method. Friction and wear tests were conducted with a pin-on-disk contact configuration with an elevated temperature friction and wear tester. The morphologies of the worn surfaces were observed by scanning electron microscopy and a non-contact three-dimensional surface profiler. The crystalline structure, thermal properties, and mechanical properties were comparatively investigated. The results showed that the thermal endurance, friction-reducing capacity, and wear resistance were improved with the addition of TPI. It was found that the wear rate of the blends was dominated by the wear temperature rather than the wear tester contact pressure. The wear mechanism transferred from abrasive wear to adhesive wear when the environmental temperature exceeded the glass transition temperature. We suggest the 30% TPI/PEEK blends can be applied as a solid lubricant at elevated temperatures due to its optimum balance between compressive strength, thermal stability, and wear performance. The results could help to provide some experimental evidence for the broader application of various polymer blends affected by their wear resistance at elevated temperatures.