シリコーンゴムのトラッキング試験法の検討

抄録

This paper presents a comparison of the electrical performance of silicone rubber in two different tracking-test methods. One is a continuous tracking test which is similar to merry-go-round method. The other is an intermittent tracking test, in which the test is repeated according to the procedure of tracking test for one day and drying at 30° for two days.
In the continuous tracking test, the leakage current increases consistently due to the development of surface degradation with an increase in aging time. Meanwhile in the intermittent tracking test, the initial current value after drying is almost zero due to the recovery of surface hydrophobicity. Then weak discharges occur and the value of the current increases rapidly due to the expansion of hydrophillic area.
It is clearly demonstrated that the intermittent tracking test is more accurate for evaluating interactions of the loss and the recovery of surface hydrophobicity in the aged surface layer.