Author/Authors :
Fang، B. نويسنده Environmental Corrosion Center, Institute of Metal Research Chinese Academy of Science, Shenyang, P. R. China, 10016 and CANMET Materials Technology Laboratory 568 Booth Street, Ottawa, Ontario, Canada K1A 0G1 Fang, B. , Han، E-H. نويسنده Environmental Corrosion Center, Institute of Metal Research Chinese Academy of Sciences, Shenyang, P. R. China, 10016 Han, E-H , Elboujdaini، M. نويسنده , , Zheng، W. نويسنده , , Li، J. نويسنده CANMET Materials Technology Laboratory 568 Booth Street, Ottawa, Ontario, Canada K1A 0G1 Li, J. , Revie، R. W. نويسنده CANMET Materials Technology Laboratory 568 Booth Street, Ottawa, Ontario, Canada K1A 0G1 Revie, R. W.
Abstract :
Stress-corrosion cracking (SCC) tests were conducted in the near-neutral pH standard solution, NS4, and in an actual soil solution, using four-point bending at a high stress ratio and low frequency conditions very similar to those of operational pipelines. Pitting incubation appeared first and then pitting initiated and grew in both solutions although there were many more pits on the specimen tested in soil purged with 5% CO2 +95%N2 than in the specimen tested in NS4 solution purged with the same gas. These observations show that samples in soil solution are more susceptible to pitting than those in NS4 solution. When the pit reached a critical size, the increased stress concentration around the pits, resulted in transition to a crack.
