Void coalescence and fracture behavior of notched and un-notched tensile tested specimens in fine grain dual phase steel

In this study, a hybrid experimental and numerical investigation is implemented to characterize the plasticity and ductile fracture behavior of a high-strength dual-phase steel. Uniaxial tensile tests are conducted along the three typical directions of rolled sheet metals for the anisotropic plastic behavior, while the hydraulic bulge test is applied for the flow behavior under equiaxial biaxial tension. Further tensile tests are conducted on various featured dog-bone specimens to study the fracture behavior of the material from the uniaxial to plane-strain tension. On the numerical side, the evolving non-associated Hill48 (enHill48) plasticity model considering anisotropic hardening and plastic strain ratio evolution is employed to describe the anisotropic plastic deformation. The extended enHill48 model with damage and fracture formulation is further calibrated and validated in the study to describe the ductile fracture behavior of the steel under various stress states. Through a comparison of the results based on the evolving anisotropic model with the isotropic Mises model, it is concluded that even for materials that show only minor initial plastic anisotropy, it could develop a non-negligible influence on the large plastic deformation and the prediction of both deformation and fracture shows profound improvement with the evolving anisotropic plasticity model.

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Experimental investigation of void coalescence in a dual phase steel using X-ray tomography

Acta Materialia ◽

10.1016/j.actamat.2013.07.058 ◽

2013 ◽

Vol 61 (18) ◽

pp. 6821-6829 ◽

Cited By ~ 35

Author(s):

C. Landron ◽

O. Bouaziz ◽

E. Maire ◽

J. Adrien

Keyword(s):

Experimental Investigation ◽

Dual Phase Steel ◽

Void Coalescence ◽

Dual Phase ◽

X Ray

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Effects of Finish-Rolling Reduction on Microstructure and Mechanical Properties for C-Si-Mn Hot Rolled Dual-Phase Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.339.215 ◽

2011 ◽

Vol 339 ◽

pp. 215-218

Author(s):

Bin Bin Sun ◽

Zhi Wei Jia ◽

Hong Mei Zhang

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Dual Phase Steel ◽

Lath Martensite ◽

Rolling Reduction ◽

Dual Phase ◽

Fine Grain ◽

Microstructure And Mechanical Properties ◽

Finish Rolling ◽

Hot Rolled

The experiments were carried out on the φ450 hot rolling mill at the State Key laboratory of Rolling and Automatic of Northeastern University. The effect of different finish-rolling reduction on the microstructure and mechanical properties of C-Si-Mn hot rolled dual-phase steel were studied. It is found that the grain size of the ferrite would be finer with the increasing of finish-rolling reduction. Through the controlling of the finish-rolling reduction, grain size of the ferrite can be finer, so the better properties can be obtained by fine grain and sub-grain strengthened. With the low volume of lath martensite, the elongation of sample is high, the yield-strength ratio is low, and complex properties are better.

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Fracture behavior of a tempered dual phase steel

Metallography ◽

10.1016/0026-0800(84)90016-8 ◽

1984 ◽

Vol 17 (2) ◽

pp. 123-130 ◽

Cited By ~ 10

Author(s):

O.R. Jardim ◽

W.P. Longo ◽

K.K. Chawla

Keyword(s):

Fracture Behavior ◽

Dual Phase Steel ◽

Dual Phase

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Microstructure and Property Control of Hot Rolled DP600 Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.415-417.938 ◽

2011 ◽

Vol 415-417 ◽

pp. 938-942

Author(s):

Le Yu Zhou ◽

Ya Zheng Liu ◽

Lian Hong Yang ◽

Dan Zhang

Keyword(s):

Dual Phase Steel ◽

Volume Fraction ◽

Ferrite Matrix ◽

Accelerated Cooling ◽

Dual Phase ◽

Dp Steel ◽

Fine Grain ◽

Mechanical Experiment ◽

Property Control ◽

Hot Rolled

Thermal mechanical experiment of step-cooling of 600MPa hot-rolled DP steel after compressed was carried out on Gleeble-1500 thermal mechanical simulator, using design of butterfly-shaped sample. Microstructure evolution during step-cooling and its effect on mechanical property of tested steel were analyzed. It is shown that, dual phase microstructure which martensite islands disperses in fine grain ferrite matrix is obtained by holding for 8~10s at 670°C followed accelerated cooling to 200°C. With increasing of holding time, grain size of ferrite coarsens, and volume fraction of ferrite has few changes. Meanwhile, tensile strengths of tested steel are all near 600MPa. That is to say, ferrite transformation is adequate during holding for 8~10s at 670°C and tensile strength of dual phase steel is stable accordingly.

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