STRESS CORROSION CRACKING

DISCUSSION ON SESSION 2

M.A. CORDOVI Chairman

The voluminous static autoclave corrosion data reported during the past few years have, of course, been generated under simulated conditions which are much more severe than one would normally expect in actual service. While the result of such investigations therefore cannot be used directly to predict service behaviour, nevertheless they do serve a most useful function by indicating trends ensuing from variations in certain parameters (temperature stress, crevices, thermal treatment contaminants etc.) which singly, or in combination, may have a significant influence on the design life of the equipment. What seems to be required in future programmes along the same lines would be a repetition of some of the tests but with the specific aim of determining threshold conditions below which the failures previously observed would not recur within the same test period. Information derived from such investigations should be of considerable value with respect to design considerations, fabrication practices and control of contaminants. Supplementing such programmes it would be very desirable indeed, and to everyone's benefit, if service failures when they occurred be promptly and carefully detailed by the operating company so that an effort can then be made to correlate thes«e occurrences with the observations previously made in the laboratory.