Effect of low temperature tensile properties on crack driving force for Arctic applications

• Published in: Theoretical and applied fracture mechanics Vol. 93; pp. 88 - 96
• Main Authors: Dahl, B.A., Ren, X.B., Akselsen, O.M., Nyhus, B., Zhang, Z.L.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ltd 01-02-2018; Elsevier BV
• Subjects: Arctic materials; Crack driving force; Finite element method; Impact analysis; Low temperature; Lüders plateau; Mathematical models; Petroleum; Strain; Studies; Temperature dependence; Tensile properties; Tensile strength; Tension; Yield strength; Arctic region; Crack driving force; Tensile properties; Lüders plateau; Arctic materials; Low temperature
• ISSN: 0167-8442; 1872-7638
• DOI: 10.1016/j.tafmec.2017.07.006

•Effects of low temperature on the crack driving force in steels investigated.•Increase of Lüders strain will increase crack driving force.•Crack driving force as a function of yield strength, Lüders strain and loading is proposed.
Many petroleum companies expand their activities further north towards the Arctic region, resulting in design temperatures down to −60°C, which is much lower than what is usual for most current petroleum installations. As properties of steels are temperature dependent, it is of great interest to evaluate the effects of low temperature on the crack driving force in steels. The present work investigates these effects numerically using a finite element model of a single-edge-notched-tension (SENT) specimen with crack depth a/W=0.5. The effects of Lüders strain and yield strength are studied for gross stress levels σG/σy≤0.5, and it is shown that an increase in yield strength and Lüders strain, as a result of Arctic temperature, intensifies the crack driving force. An approximate model that can be used to estimate the crack driving force based on yield strength, Lüders strain and loading is proposed.