A Quantitative Method for Determining the Resistance of Polymers to Surface Discharges

A method has been developed to characterize the resistance of polymers to erosion by surface discharges. It was found possible to produce surface discharges on wet, contaminated surfaces without the usual disturbing influences of metal electrodes and wetting agents. Instrumentation was devised to monitor continuously the electrical behavior of the test specimens. The test yields a quantitative erosion rate in mg/C which is characteristic of the material and test conditions used. In addition, the electrical measurements permit the detection of long-term changes in the surface properties. A method is proposed to use the test in conjunction with outdoor test station data to obtain an estimate of service life.