大電流通電、摺動における接点劣化挙動

抄録

In this study, we investigated the degradation behavior of contacts based on the contact resistance and temperature change during high current using Sn plating used in automotive terminals. In the non–sliding energization test, there was a positive correlation between the current value and the temperature rise, and it was confirmed that the temperature rise exceeded 20°C and the contact resistance decreased. It is considered that the plating softened, and the contact area was deformed due to the effect of current generation caused by increased current value. And the contact resistance decreased due to the increase in contact area. Next, it was confirmed that the slight sliding wear phenomenon as in the well–known low current energization occurs in the energization accompanied by sliding. However, the higher the current value, the shorter the number of slides until the base material is exposed. Under the high–current condition, the heat effect is large, which accelerated the softening and melting of the contact area and accelerated the abrasion of the plating.

Based on these results, the higher the current value, the higher the calorific value generated, which causes the plating film to soften and an increment in contact area. Therefore, it is expected that the plating wear will progress more, especially under the slight sliding conditions caused by the vibration of the vehicle body, and the result is consistent with the concern in actual use.