Nanoindentation investigation of temperature effects on the mechanical properties of Nafion® 117

Abstract

Operating temperature can be a limiting factor in reliable applications of Proton ExchangeMembrane (PEM) fuel cells. Nanoindentation tests were performed on perfluorosulfonic acid (PFSA)membranes (Nafion® 117) in order to study the influence of the temperature condition on theirmechanical properties. The hardness and reduced modulus of Nafion® 117 were measured withina certain temperature range, from 10 to 70°C. The results indicate that both hardness and elasticmodulus show non-monotonic transition with the increase of the test temperature, with reachingpeak values of 0.143 and 0.833 GPa at 45°C. It also found that the membranes have a shape memoryeffect and a temperature dependent shape recovery ratio.