Abstract: An electrode is mounted in a vertical manner in an electrolytic liquid in an electrolytic cell. A harmful gas collecting hood is disposed within the electrolytic cell to cover the entire upper portion of the electrode. One end of a bottom surface of the hood lies at a higher location than the other end of the bottom surface of the hood. An inlet of a harmful gas treating pipe line is disposed in the vicinity of that portion of the bottom surface of the hood which lies at the higher location thereof. A harmful gas generated around the electrode is smoothly guided to the inlet by a guide effect of the hood and sucked into the inlet.

Abstract: It is an object of the present invention to provide a corrosion resistance test process, wherein the estimation of the corrosion resistance of an article formed of a metal material and a coating can be carried out synthetically and in a short time. In carrying out a corrosion resistance test, the article is immersed into an electrolytic solution and then, a voltage is applied to the metal material to carry out a metal material corroding step and a coating peeling-off step alternatively and repeatedly. The voltage applied to the metal material is a superimposed voltage Vd+Va resulting from superimposition of a DC voltage Vd and an AC voltage Va. A voltage condition of Vd<0 and Vd+Va>0 is established at the metal material corroding step, while a voltage condition of Vd<0 and Vd+Va<0 is established at the coating peeling-off step.