A study of stress-corrosion cracking by Wedge-force loading

✍ Scribed by H.R. Smith; D.E. Piper; P.K. Downey

• Publisher: Elsevier Science
• Year: 1968
• Tongue: English
• Weight: 491 KB
• Volume: 1
• Category: Article
• ISSN: 0013-7944
• DOI: 10.1016/0013-7944(68)90019-2

✦ Synopsis

Ah&act

-Traditional stresscorrosion tests involving smooth specimens are rapidly being rephtced by tests derived from fracture mechanics. Although the opinion is widely held that stresscorros ion cracking (SEC) is dependent upon an applied crack-tip stress-intensity factor, it can be argued that the dependency is with net-section stresses. Wedge-force loading a center cracked sheet specimen provides a unique resolution of the question. In this system, crack extension causes a decreasing stress-intensity factor at the crack tip, whik at the same time, net-section stresses increase. Therefore, when stress-corrosion crack growth arrests in this specimen, the dependency on stress-intensity is proven. The stress-intensity at arrest is found to agree remarkably well with K, values determined by more conventional techniques wherein crack initiation thtesholds are established by multiple tests. Crack growth rate data important to the establishment of inspection intervals in structure can also be obtained. Finally, the technique affords considerable economy of test time and material costs in stress-corrosion studies.