Dynamic Recrystallization (<scp>DRX</scp>) Analysis of Heavy Reduction Process with Extra‐<scp>T</scp>hickness Slabs

Zhao, Xueping; Zhang, Jiongming; Lei, Shaowu; Wang, Yuanning

doi:10.1002/srin.201300277

Cited by 16 publications

(11 citation statements)

References 31 publications

(38 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The relationship between ln Z and ln ϵ c and ln ϵ p was shown in Figure , and expressed in Equation –3. The kinetic model of dynamic recrystallization for Nb–Ti microalloyed steel can be also established using Johnson‐Mehl‐Avrami (JMA) equation, which was expressed in Equation

Z = \overset{ϵ}{true} \cdot \exp true(\frac{331293}{8.314 \times T} true)

ϵ_{c} = 0.02375 Z^{0.0619}

ϵ_{p} = 0.01610 Z^{0.1088}

X = 1 - \exp true[- 0.38456 {false(\frac{ϵ - ϵ_{c}}{ϵ_{p}} false)}^{^{^{_{_{_{^{4.442}}}}}}} true]

where ϵ c and ϵ p are critical strain and peak strain, respectively;

true \dot{ϵ}

is the strain rate, s −1 ; Z is Zener‐Hollomon parameter; T is the temperature, K; X is the recrystallization volume fraction.…”

Section: Discussionmentioning

confidence: 99%

“…Recrystallized grain size can be expressed as a function of deformation temperature and strain rate. The correlation between austenite grain size and deformation parameters can be expressed as follows:

d_{r e x} = a_{1} d_{0}^{a_{2}} {true \dot{ϵ}}^{a_{3}} \exp true(\frac{Q}{R T} true)

where d 0 is the initial grain size, µm; T is the deformation temperature, K; R is the universal gas constant, J(mol −1 k −1 ); Q is the activity energy, J mol −1 ; a 1 , a 2 , and a 3 are constants. The average initial austenite grain size was measured to be 650 µm.…”

Section: Discussionmentioning

confidence: 99%

“…Dynamic recrystallization (DRX) occur during hot deformation, when the accumulative strain energy on account of the build‐up of dislocations reaches a critical value, DRX starts . After its initial, the volume fraction of DRX is increased rapidly with increasing strain . It can be seen from Figure , the established dynamic recrystallization model was used to reflect dynamic recrystallization behavior at higher deformation temperature ranging from 1200 to 1400 °C and strain rate ranging from 0.0001 to 1 s −1 .…”

Section: Analysis Of Dynamic Recrystallization During Hhr Rolling Promentioning

confidence: 99%

“…Recently, a novel rolling technology called Hot‐core Heavy Reduction (HHR) has been developed to refine the center microstructure in continuously cast slab, which is directly rolling slab at the end of solidification and with large temperature gradient. Hot‐core Heavy Reduction (HHR) is a rolling process with large deformation resistance gradient . When rolling process starts, the center temperature of the slab is still high, but surface temperature decreases very quickly.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Evolution of Austenite Grain Size in Continuously Cast Slab during Hot‐Core Heavy Reduction Rolling Process Based on Hot Compression Tests

Gong

Wang

et al. 2018

steel research int.

View full text Add to dashboard Cite

A novel technology called Hot‐core Heavy Reduction (HHR) has been developed to refine the center microstructure of continuously cast slabs, which is rolling at the end of solidification and with large temperature gradient. In this work, plant trials of Hot‐core Heavy Reduction rolling is conducted and show the significant refinement effect on the center microstructure of continuously cast slab. Dynamic recrystallization behavior in Nb–Ti microalloyed slab at high deformation temperature of 1000–1300 °C is further understood using Gleeble‐3800 thermo‐mechanical simulator. The results show that all the austenite grains are largely refined after deformation in hot compression tests. Austenite grains present different morphologies under different deformation temperature. At the temperature of 1100 °C, austenite grains can be significantly refined with increase in the strain and strain rate. While at higher deformation temperature of 1300 °C, austenite grain size cannot be further refined but become coarse to some extent when strain increases to 0.8 and strain rate increases to 10 s−1. Moreover, the dynamic recrystallization model and austenite grain size model are established in the deformation process. Then, the dynamic recrystallization volume fraction and austenite grain size during HHR rolling process can be well reflected by the established models.

show abstract

Z = \overset{ϵ}{true} \cdot \exp true(\frac{331293}{8.314 \times T} true)

ϵ_{c} = 0.02375 Z^{0.0619}

ϵ_{p} = 0.01610 Z^{0.1088}

X = 1 - \exp true[- 0.38456 {false(\frac{ϵ - ϵ_{c}}{ϵ_{p}} false)}^{^{^{_{_{_{^{4.442}}}}}}} true]

where ϵ c and ϵ p are critical strain and peak strain, respectively;

true \dot{ϵ}

is the strain rate, s −1 ; Z is Zener‐Hollomon parameter; T is the temperature, K; X is the recrystallization volume fraction.…”

Section: Discussionmentioning

confidence: 99%

d_{r e x} = a_{1} d_{0}^{a_{2}} {true \dot{ϵ}}^{a_{3}} \exp true(\frac{Q}{R T} true)

Section: Discussionmentioning

confidence: 99%

Section: Analysis Of Dynamic Recrystallization During Hhr Rolling Promentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Evolution of Austenite Grain Size in Continuously Cast Slab during Hot‐Core Heavy Reduction Rolling Process Based on Hot Compression Tests

Gong

Wang

et al. 2018

steel research int.

View full text Add to dashboard Cite

show abstract

“…Therefore, POSCO provided a type of flexible HR method, which was executed by several segments at the strand solidification end, and the maximum reduction rate was 30 mm/min. 9 Zhao et al 10,11 proposed a new HR approach, called the heavy reduction process to improve segregation and porosity (HRPISP), and they simulated the deformation and dynamic recrystallization (DRX) behavior of the HR process of the extra-thick slab by using the THERCAST.…”

Section: Introductionmentioning

confidence: 99%

Thermo-Mechanical Behavior of the Continuous Casting Bloom in the Heavy Reduction Process

Zhu

2016

JOM

View full text Add to dashboard Cite

A two-stage sequential heavy reduction (HR) method, in which the reduction amount was increased both before and after the solidification end, is presented to simultaneously improve the homogeneity and compactness of the continuous casting bloom. With bearing steel GCr15 chosen as the specific research steel, a three-dimensional thermal-mechanical finite element model was developed to simulate and analyze the thermal and mechanical behaviors of the continuous casting bloom during the HR process. In order to ensure the accuracy of the simulation, the constitutive model parameters were derived from the experimental results. The predicted temperature distribution and shell thickness were verified using a thermal infrared camera and nail shooting results, respectively. The real measured relationship between the HR pressure and amount were applied to verify the mechanical model. The explorative application results showed that the quality of the bloom center and compactness of rolled bars have both been significantly improved after the HR was applied.

show abstract

Influence of Heavy Reduction (HR) on the Internal Quality of the Bearing Steel GCr15 Bloom

Ji¹,

Wu²,

Zhu³

2016

CFD Modeling and Simulation in Materials Processing 2016

View full text Add to dashboard Cite

Dynamic Recrystallization (DRX) Analysis of Heavy Reduction Process with Extra‐Thickness Slabs

Cited by 16 publications

References 31 publications

Evolution of Austenite Grain Size in Continuously Cast Slab during Hot‐Core Heavy Reduction Rolling Process Based on Hot Compression Tests

Evolution of Austenite Grain Size in Continuously Cast Slab during Hot‐Core Heavy Reduction Rolling Process Based on Hot Compression Tests

Thermo-Mechanical Behavior of the Continuous Casting Bloom in the Heavy Reduction Process

Influence of Heavy Reduction (HR) on the Internal Quality of the Bearing Steel GCr15 Bloom

Contact Info

Product

Resources

About