Discussion on “The Influence of Stress on Corrosion,” by Julius J. Harwood. Corrosion, 6, No. 8, 249-59 and No. 9, 290-307 (1950) Aug. and Sept.
Comment by John W. Ryznar, National Aluminate Corp., Chicago, Ill.
Mr. Harwood has pointed out a number of factors which tend to substantiate an electrochemical mechanism of stress corrosion cracking.
I would like to bring out one additional factor and that is that at least one type of stress corrosion cracking can be controlled by use of suitable chemical inhibitors.
This is the type commonly known as caustic embrittlement or intercrystalline cracking of steel. The essential conditions for this type of cracking is the presence of a high concentration of caustic soda with some silica in contact with steel under high tensile stress. These conditions are often encountered in steam generating boilers. This type of cracking can be readily prevented by use of sufficient...