Relating matrix stress to local stress on a hard microstructural inclusion for understanding cleavage fracture in high strength steel

Relating matrix stress to local stress on a hard microstructural inclusion for understanding cleavage fracture in high strength steel

Jiang, Quanxin (TU Delft Team Vera Popovich)
Morete Barbosa Bertolo, V. (TU Delft Team Vera Popovich)
Popovich, V. (TU Delft Team Vera Popovich)
Sietsma, J. (TU Delft Team Kevin Rossi)
Walters, C.L. (TU Delft Ship Hydromechanics and Structures; TNO)

2021

Macroscale cleavage fracture toughness of high strength steels is strongly related to the fracture of hard microstructural inclusions. Therefore, an accurate determination of the local stress on these inclusions based on the matrix stress is necessary for the statistical modelling of macroscale cleavage fracture. This paper presents analytical equations to quantitatively estimate the stress of the microstructural inclusions from the far-field stress of the matrix. The analytical equations account for the inclusion shape, the inclusion orientation, the far-field stress state and matrix material properties. Finite element modelling of a representative volume element containing a hard inclusion shows that the equations provide an accurate representation of the local stress state. The equations are implemented into a multi-barrier model and compared with CTOD experiments with two different levels of constraint.

Cleavage fracture
Hard inclusion
High strength steel
Microstructure

http://resolver.tudelft.nl/uuid:7f79d387-2428-4613-8063-77b1216ec70d

https://doi.org/10.1007/s10704-021-00587-y

0376-9429

International Journal of Fracture, 232 (1), 1-21

Institutional Repository

journal article

© 2021 Quanxin Jiang, V. Morete Barbosa Bertolo, V. Popovich, J. Sietsma, C.L. Walters