온도변화에 따른 주석 도금한 전기 커넥터의 미동마멸 부식 거동

Abstract

In this study, we conduct fretting corrosion tests on tin-plated brass coupons to investigate the effectof temperature on fretting corrosion for various span amplitudes. We prepare a coupled fretting corrosion specimensusing a tin-plated brass coupon with a thickness of 10 μm. One specimen is a flat coupon and the otherspecimen is a coupon with a protuberance in 1 mm radius, which is produced using 2 mm diameter steel ball. We conduct fretting corrosion tests at 25oC, 50oC, 75oC, 100oC by rubbing the coupled coupons together at thecontact between the flat and protuberance coupons. We measure electric resistance of the contact during the frettingcorrosion test period. There is increase in resistance with fretting cycles. It is found that rate of increase inelectric resistance becomes faster with increase in testing temperature. Magnitude of friction coefficient increaseswith fretting span amplitudes. And, change in friction coefficient becomes desensitized to the increment in spanamplitude. Assuming that failure cycle is the cycle with an electric resistance of 0.01 Ω, we find that failure lifetime(Nf) decreases with increase in testing temperature. Furthermore, based on the assumption that the damagerate of the connector is inversely related to the failure cycle, we calculate the activation energy for fretting damageto be 13.6 kJ/mole by using the Arrhenius equation. We propose a method to predict failure cycle at differenttemperatures for span amplitudes below 30 μm. Friction coefficients generally increase with increase in spanamplitude and decrease in testing temperature.