NUMERICAL DETERINATION OF CRACK INITIATION MOMENT IN CHARPY SPECIMENS AND SIDE-GROOVED SPECIMENS
DOI:
https://doi.org/10.20535/2305-9001.2015.73.38313Keywords:
Charpy specimen, edge notch specimen, finite element method, Gurson–Tvergaard–Needleman damage material model, crack initiation point, fracture mechanismAbstract
Purpose. The object of the presented work is the finite element analysis of Charpy impact tests in the two-dimensional and three-dimensional formulations.
Design/methodology/approach. Charpy specimens impact tests are one of more simple and inexpensive method to determine the mechanical properties of materials. The results of these tests can be used to estimate the strength and durability of large-scale structures. Numerical simulation of Charpy specimens impact test can give more information about the features of crack initiation and propagation in materials under dynamic loading.
Findings. Numerical modelling of Charpy specimens impact tests was performed using Gurson–Tvergaard–Needleman (GTN) damage material model. Local approach to fracture allows to obtain crack initiation point data inside the specimen and on an edge side of the specimen. Using variable parameters of GTN model one can simulate crack initiation and propagation under different fracture mechanism. Present work describes an estimation of the crack initiation point under brittle, ductile, quasi-brittle fracture mechanisms using GTN model.
Originality/value. The results of numerical modelling of Charpy specimens impact test can be used to evaluate the strength and life time of construction elements.
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