Creviced Bent Beam

The standard testing for SCC has been reviewed by Sedriks [9] and Turnbull [10]. The following techniques have been used to estimate the SCC surface flawed, cantilever bend, creviced bent-beam tests, double cantilever beam, and compact tension specimens. 

Therefore, a new stress corrosion cracking test method was developed (Creviced Bent Beam CBB test), which considers the crevice effect as well as factors B, C and D above. Bend test specimens with an artificial crevice made from graphite wool (more sensitive than those made from PETE and especially metal-metal) were tested (both welded and non-welded but sensitised at 600 C/2 h) in high purity water with 0.2 pS/cm, oxygen saturated, chloride < 0.1 mg/1, pH S.8-6.2 at 250 C. For more than 20 steel specimens with different carbon contents (which are responsible for various susceptibilities to sensitisation) one obtains very clear conclusions from 20 specimens each of them showed stress corrosion cracking after only 24 hours, so long as the carbon content lied in the range 0.06-0045%. In the process cracks with... 

The influence of the potential on the susceptibility to stress corrosion cracking of sensitised (615 °C/10 h) filler materials made of Alloy 182 (67 Ni, 14.12 Cr, 7.44 Mn, 7.43 Fe, 0.41 Ti, 1.95 Nb) in high purity water with < 0.2 pS/cm, pH 6, at oxygen contents up to 200 mg/1 and 288 °C was examined [168]. Test methods included CERT tests and CBB (creviced bent beam) tests. The potential was adjusted using oxygen dosing, see Figure 27. 

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