Numerical Study of the Crack-Front Constraint for SENT Specimens of X80 Pipeline Steel

Abstract:

This work presents a numerical study of crack-front constraint for SENT specimens of X80 pipeline steel, to examine geometry effect on the correlation of crack-front stress field and constraint. An average measure of constraint over crack-front A_m was employed to characterize the crack-front constraint. SENT specimens with varying geometries (different crack depth to specimen width ratio, a/W, and different specimen width and thickness, W/B) were analyzed by Gurson-Tvergaard-Needleman model (GTN model). Results showed that the stress triaxiality A_m can characterize the crack-front constraint of X80 pipeline steel very well. The level of the A_m-△a curve rises with the decrease of crack depth, and increases first and then decreases with the increase of SENT specimen thickness.

• Periodical: Materials Science Forum (Volume 898)
• Pages: 735-740
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.898.735
• Online since: June 2017
• Authors: Ting Zhong*, Lin Zhu, Yan Zhou, Jian Shuai, Lan He
• Keywords: Crack-Front Constraint, Finite Element Analysis, Geometry Effect, SENT Specimens, X80 Pipeline Steel

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