Effect of hardening models on different ductile fracture criteria in sheet metal forming

2016-07-01
Dizaji, Shahram Abbasnejad
Darendeliler, Haluk
KAFTANOĞLU, BİLGİN
Prediction of the fracture is one of the challenging issues which gains attention in sheet metal forming as numerical analyses are being extensively used to simulate the process. To have better results in predicting the sheet metal fracture, appropriate ductile fracture criterion (DFC), yield criterion and hardening rule should be chosen. In this study, the effects of different hardening models namely isotropic, kinematic and combined hardening rules on the various uncoupled ductile fracture criteria are investigated using experimental and numerical methods. Five different ductile fracture criteria are implemented to a finite element code by the user subroutines. The criterion constants of DFCs are obtained by the related experimental tests. The in-plane principle strains obtained by the finite element analyses for different DFCs are compared with the experimental results. Also, the experimental results are used to evaluate the principle strain values calculated by the finite element analysis for different combinations of DFCs and hardening rules. It is shown that some DFCs give better predictions if the appropriate hardening model is employed.
INTERNATIONAL JOURNAL OF MATERIAL FORMING

Suggestions

Effect of curvature on lower extremity residual limb models
Tönük, Ergin (null; 1999-12-01)
Indentor tests are one of the most common ways for in vivo estimation of human residual limb soft tissue bulk elastic and viscoelastic material properties. Due to large strains and displacements encountered during indentation, elementary strength of materials approaches yield crude approximations of the material properties. A common procedure, therefore, is to construct a finite element model of the tissue in the vicinity of the test site. The material properties of soft tissue are identified by matching th...
Effect of constitutive modeling in sheet metal forming
Uçan, Meriç; Darendeliler, Haluk; Department of Mechanical Engineering (2011)
This study focuses on the effects of different constitutive models in sheet metal forming operations by considering the cylindrical and square cup drawing and V-bending simulations. Simulations are performed using eight different constitutive models; elastic plastic constitutive model with isotropic hardening, elastic plastic constitutive model with kinematic hardening, elastic plastic constitutive model with combined hardening, power law isotropic plasticity, piecewise linear isotropic plasticity, Barlatth...
Effects of geometric factors on mode I fracture toughness for modified ring tests
Tutluoğlu, Levend (2012-04-01)
Stress intensity factors of specimen models with various external diameters, inner hole diameters, and extents of flattened loading boundaries for the modified ring testing method for mode I fracture are computed by finite element modeling. Effects of boundary conditions and geometric factors on stress intensity factor computation are analyzed. Parametric expressions are proposed to estimate critical crack length position and corresponding maximum stress intensity factor. An expression in terms of inner hol...
Effect of swaging on microstructure and tensile properties of W-Ni-Fe alloys
DURLU, NURİ; Caliskan, N. Kaan; Bor, Sakir (Elsevier BV, 2014-01-01)
The objective of this study was to investigate the effect of swaging on the microstructure and tensile properties of high density two phase alloys 90W-7Ni-3Fe and 93W-4.9Ni-2.1Fe. Samples were liquid phase sintered under hydrogen and argon at 1480 degrees C for 30 min and then 15% cold rotary swaged. Measurement of microstructural parameters in the sintered and swaged samples showed that swaging slightly increased tungsten grain size in the longitudinal direction and slightly decreased tungsten grain size i...
Effect of microstructural modification on damage tolerance of 34CrMo4 shaft steel
Ozcan, Burak; Gurer, Goksu; Gür, Cemil Hakan (Wiley, 2020-06-01)
Overall damage tolerances of the heat-treated 34CrMo4 steels having ferritic-pearlitic, bainitic, and tempered-martensitic microstructures were evaluated based on their threshold stress intensity factor prior to small crack propagation, fatigue strength, and fracture toughness under static loading. Kitagawa-Takahashi diagrams were constructed to determine the limiting size of small crack propagation. The micromechanical effects of carbide morphology and phase distribution on quasi-static and dynamic mechani...
Citation Formats
S. A. Dizaji, H. Darendeliler, and B. KAFTANOĞLU, “Effect of hardening models on different ductile fracture criteria in sheet metal forming,” INTERNATIONAL JOURNAL OF MATERIAL FORMING, pp. 261–267, 2016, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/41405.