This project aims to find alternative materials to Teflon(PTFE) that are PFAS-free material to be used for the ball valve seat components used by Belimo Technology Inc. PTFE is used for its excellent tribological properties, sealing performance, and chemical stability. However, PTFE contains PFAS compounds that are expected to have restrictions due to environmental and health concerns. The objective of this project is to evaluate alternative PFAS-free materials that can match or exceed the performance characteristics of PTFE. This joint project between Mechanical Engineering (ME) and Materials Science and Engineering (MSE) students divides testing responsibilities across key performance attributes. The ME team will evaluate both static and kinetic coefficient of friction using a test following the standardized test ASTM D1894, wear resistance using a Junkers vibration test machine, and sealing performance through the pressure drop of a pressurized vessel. The MSE team will evaluate the temperature ranges using Differential Scanning Calorimetry (DSC), chemical resistance through exposure testing in both 100% water and a 50% water–50% propylene glycol solution, and creep resistance using a three-point bend test following the standardized test ASTM D790. Candidate materials including UHMWPE, HDPE, PEEK, Delrin, and Nylon will be tested and compared against baseline PTFE performance. The results will be compared to provide recommendations for viable PFAS-free alternatives.

Our team collaborated with Materials Science & Engineering 9 on this project.