A finite element analysis for asymmetric contraction after coiling of hot-rolled steel

Asymmetric contraction during natural cooling is often observed after the coiling of hot-rolled steel, which has significantly large hardenability due to high content of carbon or other alloying elements. In this study, a finite element (FE) model incorporating transformation plasticity was used to analyze the thermo-mechanical and metallurgical behavior of hot-rolled steel during the phase transformation after coiling. The transformation plasticity was caused by a small amount of stress that develops naturally in a hot-rolled coil due to the gravity. The asymmetric contraction behavior of the coil was reproduced successfully using the FE simulation by considering the transformation plasticity. The effect of some selected process variables on the asymmetric contraction was examined through a series of process simulations.

[1]  D. Suh,et al.  Diffusion-controlled transformation plasticity of steel under externally applied stress , 2007 .

[2]  J. Mize.  Optimization Techniques With Fortran , 1973 .

[3]  E. Scheil,et al.  Anlaufzeit der Austenitumwandlung , 1935 .

[4]  D. Suh,et al.  Dilatometric Analysis of Phase Fraction during Austenite Decomposition into Banded Microstructure in Low-Carbon Steel , 2007 .

[5]  Jae Kon Lee,et al.  A Constitutive Model for Transformation Superplasticity under External Stress during Phase Transformation of Steels , 2002 .

[6]  Kyu Hwan Oh,et al.  Finite Element Analysis of Hot Rolled Coil Cooling , 1998 .

[7]  Gyung-Jin Park,et al.  Thermal analysis of the roll in the strip casting process , 2003 .

[8]  Tae-Ho Lee,et al.  A model for deformation behavior and mechanically induced martensitic transformation of metastable austenitic steel , 2004 .

[9]  D. Suh,et al.  Dilatometric analysis of austenite decomposition considering the effect of non-isotropic volume change , 2007 .

[10]  J. Ågren.  A revised expression for the diffusivity of carbon in binary FeC austenite , 1986 .

[11]  H.N. Han,et al.  Model for cooling and phase transformation behaviour of transformation induced plasticity steel on runout table in hot strip mill , 2001 .

[12]  R Morrell,et al.  Handbook of properties of technical and engineering ceramics , 1989 .

[13]  Seid Koric,et al.  Thermo-mechanical models of steel solidification based on two elastic visco-plastic constitutive laws , 2008 .

[14]  M. Ashby,et al.  Deformation-Mechanism Maps: The Plasticity and Creep of Metals and Ceramics , 1982 .

[15]  T. Courtney,et al.  Mechanical Behavior of Materials , 1990 .

[16]  G. W. Greenwood,et al.  The deformation of metals under small stresses during phase transformations , 1965, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[17]  D. Suh,et al.  A model for transformation plasticity during bainite transformation of steel under external stress , 2003 .

[18]  Ahmad Saboonchi,et al.  Heat transfer analysis of hot-rolled coils in multi-stack storing , 2007 .

[19]  Jian Lan,et al.  Researches on the ring stiffness condition in radial–axial ring rolling , 2009 .

[20]  D. Suh,et al.  Diffusion-controlled recrystallization and grain growth-induced plasticity of steel under externally applied stress , 2008 .

[21]  Gyung-Jin Park,et al.  Thermal crown analysis of the roll in the strip casting process , 2009 .

[22]  Jae Kon Lee,et al.  A model for deformation, temperature and phase transformation behavior of steels on run-out table in hot strip mill , 2002 .