Study of the Mechanical Behavior of Dual-Phase Steel Based on Crystal Plasticity Modeling Considering Strain Partitioning

Warm rolling at temperatures ranging from 25 °C to 500 °C was conducted on the dual-phase heterostructured low-carbon steel to investigate the effect of deformation temperature on the structural refinement and mechanical properties. Defying our intuition, the grain size and strength of the rolled steels do not deteriorate with the increase in deformation temperature. Warm rolling at 300 °C produces a much finer lamellar structure and higher strength than steels rolled at both room temperature and elevated temperature. It is supposed that the enhanced interactions between carbon atoms and defects (interfaces and dislocations) at 300 °C promote dislocation accumulation and stabilize the nanostructure, thus helping with producing an extremely finer structure and higher strength than other temperatures.

Section: Microstructures After Warm Rollingmentioning

confidence: 99%

Effect of Rolling Temperature on the Structural Refinement and Mechanical Properties of Dual-Phase Heterostructured Low-Carbon Steel

Pan

Gao

et al. 2022

“…More recently, Evin et al [27] modeled the yield strength, the uniform deformation and the true stress of DP steels based on both the volume fraction of secondary phases and the grain size of the ferrite grain. Crystal plasticity modeling was applied by Xu et al [28] to describe the response of DP steels taken into account that the volume fractions of the constituent phases and the strain partitioning function could be obtained by tensile experiments. In accordance to the previous literature review, it is possible to conclude that predictive approaches for the tensile stress-strain curve are either (i) phenomenological models based on semi-empirical laws for the composite material, or (ii) physically based models which can treat the stress-strain curve as a summation of individual contributions.…”

Section: Introductionmentioning

confidence: 99%

Modeling the Mechanical Response of a Dual-Phase Steel Based on Individual-Phase Tensile Properties

Alvarez

Muñoz

Celentano

et al. 2020

In this work, the engineering stress–strain tensile curve and the force-deflection bending curve of two Dual-Phase (DP) steels are modeled, combining the mechanical data of fully ferritic and fully martensitic steels. The data is coupled by a modified law of mixture, which includes a partition parameter q that takes into account the strength and strain distributions in both martensite and ferrite phases. The resulting constitutive model is solved in the context of the finite element method assuming a modified mixture rule in which a new parameter q′ is defined in order to extend the capabilities of the model to deal with triaxial stresses and strains and thus achieve a good agreement between experimental results and numerical predictions. The model results show that the martensite only deforms elastically, while the ferrite deforms both elastically and plastically. Furthermore, the partition factor q′ is found to strongly depend on the ferritic strain level. Finally, it is possible to conclude that the maximum strength of the studied DP steels is moderately influenced by the maximum strength of martensite.

“…Typical DP steels contain soft ferrite and hard martensite and they are manufactured in industry by hot or cold rolling followed by annealing [12]. The presence of martensite leads to a continuous yielding behaviour and a moderate work hardening capability [12,13]. Strength and ductility can be adjusted via controlling the volume fraction of martensite.…”

Section: Introductionmentioning

confidence: 99%

Microstructure Evolution during the Production of Dual Phase and Transformation Induced Plasticity Steels Using Modified Strip Casting Simulated in the Laboratory

Xiong

Kostryzhev

Zhao

et al. 2019

Instead of conventional steel making and continuous casting followed by hot and cold rolling, strip casting technology modified with the addition of a continuous annealing stage (namely, modified strip casting) is a promising short-route for producing ferrite-martensite dual-phase (DP) and multi-phase transformation-induced plasticity (TRIP) steels. However, at present, the multi-phase steels are not manufactured by the modified strip casting, due to insufficient knowledge about phase transformations occurring during in-line heat treatment. This study analysed the phase transformations, particularly the formation of ferrite, bainite and martensite and the retention of austenite, in one 0.17C-1.52Si-1.61Mn-0.195Cr (wt. %) steel subjected to the modified strip casting simulated in the laboratory. Through the adjustment of temperature and holding time, the characteristic microstructures for DP and TRIP steels have been obtained. The DP steel showed comparable tensile properties with industrial DP 590 and the TRIP steel had a lower strength but a higher ductility than those industrially produced TRIP steels. The strength could be further enhanced by the application of deformation and/or the addition of alloying elements. This study indicates that the modified strip casting technology is a promising new route to produce steels with multi-phase microstructures in the future.