Study of Stress Corrosion Cracking in a Pipeline Steel

Precision FIB sectioning of a pipeline steel stress corrosion cracking (SCC) test specimen allows measurement of crack length and depth. High magnification images of the FIB'd crack surface in cross section (inset) allow aspect ratios to be measured periodically without disrupting neighbouring cracks, which can then continue on for further tests in the SCC solution. Due to the very small amount of material removed during each sectioning and imaging operation, versus the large number of cracks, this process can be repeated many times over the course of a corrosion test to obtain excellent statistics from a single sample.