The effect of snow cover depth on the corrosion behavior of steels in a snowy environment was evaluated. Differences in snow-melting conditions, which due to heat derived from the height from the ground (floor of building roof) , affected the formation of water film and rust on the surface of the steel. The amount of corrosion for 100 mm was larger than that for 800 mm due to the formation of rust and the dissolution of Fe 2＋ ions caused by the maintenance of the water film. The orientation of the test surface also affected the maintenance of the water film. When the test surface was facing upward, the water film spread over the entire surface and rust occurred, while when the test surface was facing downward, rust occurred only in the area in contact with snow and the amount of corrosion was reduced.

The corrosion resistance and the oxide film of stainless steel containing Mo in simulated condensed water of oil and gas environments were investigated by electrochemical tests and X-ray photoelectron spectroscopy. From the results of potentio-dynamic polarization, Mo improved the corrosion resistance of stainless steel in simulated condensed water. From the results of electrochemical impedance spectroscopy, the oxide film of stainless steel containing Mo had fewer defects than that of stainless steel without Mo. The results of X-ray photoelectron spectroscopy showed that the oxide film containing Mo was formed in the outermost layer on Mo containing stainless steels. The thickness of the oxide film formed on stainless steel containing Mo was thinner than that of the oxide film formed on stainless steel without Mo.

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The diffusible hydrogen in the metals plays an important role in the delayed failure and hydrogen embrittlement. Therefore, the focus is on detection of hydrogen permeated through the steel in this article. The detection of permeated hydrogen electrochemically (Devanathan-Stachurski double cell) is explained in detail. It also demonstrated that the application of micro-electrochemical cell to detected permeated hydrogen during wet/dry corrosion of scratch formed zinc coated steel.

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