DEVELOPMENT OF A MICRO-SENT TEST TO DETERMINE TOUGHNESS USING X-RAY SYNCHROTRON TOMOGRAPHY

The toughness of a ductile steel (such as API 5L grade X52 vintage) used in the pipeline industry is investigated using a developed micro-SENT specimen. Micro-SENT pre-cracked samples are tested using in-situ X-ray synchrotron-radiation computed tomography (SRCT). The SRCT high resolution technique is used to provide clear images to analyse quantitatively the damage evolution during both crack initiation and crack propagation. Indeed, the crack advance is directly measured during propagation and a J-Δa resistance curve is determined. Finite Element Analysis is also used to analyse the strain fields around the crack tip and to interpret the tomography observations.