Mechanical systems utilizing hydrogen gas as energy carrier have many regulator valves. In these valves, polymer composites are used as sealing materials and sliding against metal counter faces under the gaseous hydrogen. Their friction and wear behavior in the hydrogen environment should be important as well as their hydrogen sealing ability, since the increased friction and excessive wear can induce the efficiency degradation and increase in the system maintenance cost. In this study, the gas sealing ability and wear behavior of polymer composites in gaseous hydrogen were evaluated as the index of sealing parts performance. The experimental results showed that differences in the filler materials of PTFE composites and the metal surface roughness affect both hydrogen sealing ability and volumetric wear rate.
