An extensive study was conducted of the susceptibility of austenitic stainless steels to stresscorrosion cracking in high temperature water over wide ranges of chloride and oxygen concentrations. Corrosion cracking of AISI Type 304, 304L and 347 steels was detected at considerable contents of oxygen (0.1ppm) and Cl^- (100ppm) in 300 hours at 300°C. However, the corrosion cracking of AISI 316 steel was not detected at higher contents in 300 hours. The cracking susceptibility of Type 304 steel was increased by sensitizing heat treatment.

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The applicability of the method of estimating corrosion rates from cell voltage-current curves was investigated as a rapid method to evaluate the corrosivity of industrial waters.
Cell voltage-current curves and weight losses of mild steel were measured in 30g/l sodium chloride solution containing 6.9ppm dissolved oxygen gas at 26±1°C.
It was found that the corrosion rates measured by this method were in good agreement with those found by weight loss measurement, if the sweep velocity of cell voltage was less than 100mV/min and the area ratio of anode to cathode was more than 1.
Then, corrosion rates of mild steel in the industrial waters at Kawasaki city were measured, and it was indicated that the corrosion rates measured by this method were slightly larger than those found by weight loss measurement.

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Corrosion of pure iron in steam, distilled water and alkaline solutions at temperatures of 310-350°C was studied by the weighing method. Sheet specimens were placed both in the liquid phase and in the vapor phase. The amount of iron dissolved into the liquid and that of iron oxides formed on the specimen were determined separately.
Oxygen content in the corrosion system largely affected the rate and the appearance of corroded specimens. Corrosion in the liquid phase was parabolic and the corroded surface was smooth. The transition from parabolic to linear was found for specimens in the vapor phase over alkaline solutions.
The parabolic dissolution of iron and almost constant ratio of (dissolved Fe/total Fe corroded) through reaction for specimens in the liquid phase suggest that the competing reactions between oxide growth and dissolution take place at the oxide/liquid interface. The rate transition from parabolic to linear for specimens in the vapor phase is not fully explained by Haycock's model.

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