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Table 3. Chemical analysis of the stainless steel rod used in the demonstration: composition in wt%
C Mn Si P S Cr Ni Mo
Rods 0.024 1.55 0.59 0.030 0.023 16.3 11.1 2.02
UNS S31603 0.03 2.00 1 .oo 0.045 0.030 16.0-18.0 10.0-14.0 2.00-3.00
maximum maximum maximum maximum maximum

observed in either the butanone-rich phase or the original 8 wt% water-in-butanone mixture. These
observations show that crevice corrosion had just begun to initiate in the water-rich phase, but had
not initiated in either the 8wt% solution of water in butanone, or in the butanone-rich phase formed
after the addition of water.

6. CONCLUSION
The hypothesis presented in the discussion is tenable, and can explain how crevice corrosion of
316L occurred in what was supposed to be a very dilute solution of sodium chloride in an 8 wt%
solution of water in butanone.
The unresolved question was how the additional water required to cause separation of this
solution into two immiscible liquids was introduced into the system.

REFERENCES

I. Francis, A. W., LiquicCLiquid Equilibriums. Interscience, New York, 1963.
2. Seidell, A,, Solubilities oforganic Compounds, 3rd edn. Van Nostrand, Princeton, NJ, 1941.
3. Seidell, A., Solubilities oflnorganic Compounds, 3rd edn. Van Nostrand, Princeton, NJ, 1941.