電子機器向け電気抵抗型腐食センサの開発

抄録

To diagnose the corrosiveness of an environment in which electronic equipment is installed, a new electrical-resistance type corrosion sensor with a gas-intake channel was developed. The developed sensor measures the electrical resistance of a thin metal film corroded in the gas-intake channel. In addition to utilizing the difference in electrical resistances of corroded and non-corroded metal films, the sensor takes into account the diffusion phenomenon of corrosive gas and the corrosion reaction of metals in order to convert electrical resistance to the amount of metal corrosion. If the amount of metal corrosion is obtained, the corrosiveness of the installation environment can be diagnosed on the basis of indicators defined in ISO standards and ANSI/ISA standards. Silver is sensitively reacted with reduced sulfur, which is a major factor in the risk of sulfide corrosion in electronic equipment. In this report, a corrosion sensor composed of a silver thin film was fabricated, and the performance of the sensor was evaluated by installing it in a mixed-gas environment simulating an actual machine room housing electronic equipment. According to the results of the evaluation, the amount of corrosion obtained with the new corrosion sensor agreed reasonably well with that obtained by a conventional corrosion sensor with an error of 20%. The lifespan of the corrosion sensor is twenty-times longer than that of conventional sensors, making it suitable for long-term monitoring. Moreover, it is small and inexpensive, so it can be applied at various sites where electrical equipment is installed.