Fuel Cell Elastomeric Materials Oxygen Compatibility Testing: Effect of 450 and 6200 kPa Oxygen

Abstract

The oxygen compatibility of five O-ring formulations used in the Space Shuttle oxygen/hydrogen (O2/H2) fuel cell was evaluated following exposure to 450 and 6200 kPa (65 and 900 psi) oxygen at 121 °C (250 °F) for 48 h. The elastomers tested were Neoprene compound C873-70, and four fluoroelastomers: Aflas® 7182D, Kalrez® 1045, Fluorel® 2180, and compound V884-75. Post-aging changes in mass, dimension, tensile strength, elongation at break, durometer hardness, and compression set were determined for each elastomer. Aging results were compared to ignition and combustion data, namely the autogenous ignition temperature (AIT) and heat of combustion (ΔHc). Finally, the possibility of heterogeneous oxidation is discussed.