Electrical relay in an essential part of smart grids, electrical vehicles, and LED lightning systems. Therefore, studying relay reliability is important. Relays using permanent magnet actuators (PMAs), which are energy efficient, are also in the spotlight. However, most of the permanent magnets used in PMAs have a characteristic wherein the magnetic flux decreases as the temperature increases. When the magnetic flux is reduced, the force acting on the actuator is reduced. Therefore, in this study, we measured the decrease in the relay operating speed with permanent magnet reduction due to temperature rise. In addition, changes in the bouncing phenomena due to magnetic flux reduction were analyzed. As a result, the operating speed of the relay has decreased and the bouncing phenomenon has not significantly changed.

Ti was deposited on the Al substrate using DC magnetron sputtering with changing the N2 gas for the possible application of a solar absorbing layer. N2 gas ranged from 50 to 75 sccm was systematically applied in the 5 sccm interval and the variation of the absorption rate was investigated. Microstructural examination and elemental analysis indicate that Ti was reacted with N2 gas and formed TiNOx compound. As compared with the film without any exposure of N2 gas, absorption rate improved by more than 20%. Typically the average absorption of TiNOx fim with 65% of N2 gas was about 99% in the visible range, and the average absorption was more than 90% in the infrared absorption region respectively.