This paper describes the benefits, technical difficulties and disadvantages of the current heavy reduction solutions for plate production. For updated plate mills,this paper gives a better idea for the heavy reduction...This paper describes the benefits, technical difficulties and disadvantages of the current heavy reduction solutions for plate production. For updated plate mills,this paper gives a better idea for the heavy reduction control in the rolling process. That is to keep the reduction amount constant in the front-end and back-end sections of the plate and to adopt tapered rolling with variable reduction in the middle section of the plate. This solution （ already applied for a patent） can not only fully utilize the capacity of the mill motors, but also prevent difficulties in plate biting caused by the conventional heavy reduction solutions with excessive draft. This technical solution has been implemented at the 5 m plate mill plant of Baosteel,and industrial tests have proved the feasibility of it. This paper presents and analyzes the industrial test data and proves that the tapered heavy reduction technology can reduce the number of rolling passes. In addition ,this paper looks forward to the future research in this area.展开更多
The effects of the deformation parameters in the heavy reduction(HR)process on recrystallization kinetics and microstructure evolution were analyzed.Based on the experimental results,metadynamic recrystallization(MDRX...The effects of the deformation parameters in the heavy reduction(HR)process on recrystallization kinetics and microstructure evolution were analyzed.Based on the experimental results,metadynamic recrystallization(MDRX)kinetic and austenite grain size models were established for a continuously cast slab during HR.Moreover,the evolution of the quenched microstructure after MDRX was observed using electron backscatter diffraction.The relative frequency of very low-angle grain boundaries decreased from 58.8% to 52.1%,and the relative frequency of high-angle grain boundaries increased from 28.5% to 38.9%.Analyses revealed that the recovery was the main softening mechanism.The decrease in the total grain boundary length indicated that subgrain growth occurred with increasing inter-pass time.The main texture evolved from a {001}<110>texture to a{112}<111>texture,and the texture strength remained unchanged.展开更多
Hot-core heavy reduction rolling is an innovative technology for continuous casting billet at the end of solidification.The deformation characteristics of GCr15 bearing billet were investigated over the temperature ra...Hot-core heavy reduction rolling is an innovative technology for continuous casting billet at the end of solidification.The deformation characteristics of GCr15 bearing billet were investigated over the temperature range of 1000-1300℃ with the strain rate of 0.001-10 s^(-1) by the Gleeble 3800 thermo-mechanical simulator.Firstly,the true stress-strain data are calibrated by the friction correction method to acquire accurate parameters near the solidus.Then,the Laasraoui-type constitutive model and dynamic austenite grain size model are established by the thermal compression results and corrosion experimental results,and the predicted values of the experimental interval are obtained by using the models.Meanwhile,the accuracy of models is verified by comparing the predicted curves with the experimental data.Last but not the least,the dynamic parameters between solidus and liquidus are predicted by the two models,and the difficulty of experimental collecting near the melting point is solved.展开更多
文摘This paper describes the benefits, technical difficulties and disadvantages of the current heavy reduction solutions for plate production. For updated plate mills,this paper gives a better idea for the heavy reduction control in the rolling process. That is to keep the reduction amount constant in the front-end and back-end sections of the plate and to adopt tapered rolling with variable reduction in the middle section of the plate. This solution （ already applied for a patent） can not only fully utilize the capacity of the mill motors, but also prevent difficulties in plate biting caused by the conventional heavy reduction solutions with excessive draft. This technical solution has been implemented at the 5 m plate mill plant of Baosteel,and industrial tests have proved the feasibility of it. This paper presents and analyzes the industrial test data and proves that the tapered heavy reduction technology can reduce the number of rolling passes. In addition ,this paper looks forward to the future research in this area.
基金financially supported by the National Natural Science Foundation of China(Nos.51974078,U1708259,and U20A20272)Liaoning Revitalization Talents Program(Nos.XLYC1802032 and XLYC1907176)+1 种基金the Fundamental Research Funds for the Central Universities of China(Nos.N2025012,N2125018,and N2125007)the Fourth Period Science and Technology Key Project of Panxi Experimental Area(No.PGWX2018-05).
文摘The effects of the deformation parameters in the heavy reduction(HR)process on recrystallization kinetics and microstructure evolution were analyzed.Based on the experimental results,metadynamic recrystallization(MDRX)kinetic and austenite grain size models were established for a continuously cast slab during HR.Moreover,the evolution of the quenched microstructure after MDRX was observed using electron backscatter diffraction.The relative frequency of very low-angle grain boundaries decreased from 58.8% to 52.1%,and the relative frequency of high-angle grain boundaries increased from 28.5% to 38.9%.Analyses revealed that the recovery was the main softening mechanism.The decrease in the total grain boundary length indicated that subgrain growth occurred with increasing inter-pass time.The main texture evolved from a {001}<110>texture to a{112}<111>texture,and the texture strength remained unchanged.
文摘Hot-core heavy reduction rolling is an innovative technology for continuous casting billet at the end of solidification.The deformation characteristics of GCr15 bearing billet were investigated over the temperature range of 1000-1300℃ with the strain rate of 0.001-10 s^(-1) by the Gleeble 3800 thermo-mechanical simulator.Firstly,the true stress-strain data are calibrated by the friction correction method to acquire accurate parameters near the solidus.Then,the Laasraoui-type constitutive model and dynamic austenite grain size model are established by the thermal compression results and corrosion experimental results,and the predicted values of the experimental interval are obtained by using the models.Meanwhile,the accuracy of models is verified by comparing the predicted curves with the experimental data.Last but not the least,the dynamic parameters between solidus and liquidus are predicted by the two models,and the difficulty of experimental collecting near the melting point is solved.
