Ductile fracture prediction of EH36 grade steel based on Hosford–Coulomb model

ABSTRACT

To predict ductile fracture initiation of EH36 grade high tensile strength steels, the Hosford–Coulomb ductile fracture model was employed. The ductile fracture tests were carried out on different specimen geometries: central-hole, shear specimen, and notched tensile specimens with three different notch radii. Finite element analysis was carried out for each experiment to identify hardening curve and fracture model parameters. Notched tension specimens were utilised to calibrate Swift-Voce type strain hardening function for equivalent plastic strains beyond the onset of diffuse necking. The location of the fracture initiation and corresponding loading path were investigated using finite element analysis and the test results. The Hosford–Coulomb fracture model parameters were identified using the loading paths extracted from finite element analysis results. Validation of the presented loading path dependent Hosford–Coulomb model was conducted by simulating the tests with a user-defined material subroutine implemented in the finite element analysis software package Abaqus/Explicit.

KEYWORDS:

• Word
• ductile fracture
• stress triaxiality
• Lode angle
• damage indicator
• loading path
• Hosford–Coulomb model

Notes on contributors

Sung-Ju Park is a PhD student in Naval Architecture and Ocean Engineering, Inha University.

Kangsu Lee is a Principal Research Scientist in KRISO.

Burak Can Cerik is a Research Fellow in Inha University.

Joonmo Choung is a Professor in Naval Architecture and Ocean Engineering, Inha University.

ORCID

Sung-Ju Park http://orcid.org/0000-0002-7129-8567

Burak Can Cerik http://orcid.org/0000-0003-1047-2119

Joonmo Choung http://orcid.org/0000-0003-1407-9031

Additional information

Funding

This research was supported by a grant from Endowment Project of “Study on the Core Technology of Structural Design, Engineering and Test for Establishment of Structural Evaluation System for Offshore Structure (2/3)” funded by Korea Research Institute of Ships and Ocean engineering [grant number PES3250], and Korea Research Fellowship Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT [grant number 2017H1D3A1A01055137]. This research was a part of the project titled ‘Manpower training program for ocean energy’, funded by the Ministry of Oceans and Fisheries, Korea [grant number 20140550]. This research was funded and conducted under [The Competency Development Program for Industry Specialists] of the Korean Ministry of Trade, Industry and Energy (MOTIE), operated by Korean Institute for Advancement of Technology (KIAT) [grant number N0001287].