A new method,the stream surface strip element method,for simulating the three-dimensional deformation of plate and strip rolling process was proposed.The rolling deformation zone was divided into a number of stream su...A new method,the stream surface strip element method,for simulating the three-dimensional deformation of plate and strip rolling process was proposed.The rolling deformation zone was divided into a number of stream surface(curved surface)strip elements along metal flow traces,and the stream surface strip elements were mapped into the corresponding plane strip elements for analysis and computation.The longitudinal distributions of the lateral displacement and the altitudinal displacement of metal were respectively constructed to be a quartic curve and a quadratic curve,of which the lateral distributions were expressed as the third-power spline function,and the altitudinal distributions were fitted in the quadratic curve.From the flow theory of plastic mechanics,the mathematical models of the three-dimensional deformations and stresses of the deformation zone were constructed.Compared with the streamline strip element method proposed by the first author of this paper,the stream surface strip element method takes into account the uneven distributions of stresses and deformations along altitudinal direction,and realizes the precise three-dimensional analysis and computation.The simulation example of continuous hot rolled strip indicates that the method and the model accord with facts and provide a new reliable engineering-computation method for the three-dimensional mechanics simulation of plate and strip rolling process.展开更多
The paper investigated the texture evolution of a biomedical β-titanium alloy (Ti-28Nb-13Zr-2Fe) under 15%-85% cold rolling reduction and 700°C-900°C recrystallization annealing treatment,and clarified the ...The paper investigated the texture evolution of a biomedical β-titanium alloy (Ti-28Nb-13Zr-2Fe) under 15%-85% cold rolling reduction and 700°C-900°C recrystallization annealing treatment,and clarified the effects of crystal orientation on Young’s modulus of the alloy.Orientation distribution function (ODF) maps and electron backscatter diffraction (EBSD) analysis revealed that the rolling texture type changed with the increase of reduction according to the sequence:α-fiber texture→γ-fiber texture→α-rotated cubic texture.Young’s modulus exhibited the lowest value 54 GPa under 15% reduction.Strong {111}【112】 γ-fiber texture was developed after rolling 85% reduction and annealing at 700°C,which was favorable to decreasing Young’s modulus in comparison with randomly orientated microstructure.Cyclic loading-unloading tensile test proved that the gradual rotation of {110} slip plane during plastic deformation promoted the development of {001}【110】 texture component,leading to the marked decrease of Young’s modulus.展开更多
To achieve stable rolling,the influence of a tension mechanism of a large diameter ratio roll system on the rolling process of a strip flatness electromagnetic control rolling mill is studied.Through the analysis of t...To achieve stable rolling,the influence of a tension mechanism of a large diameter ratio roll system on the rolling process of a strip flatness electromagnetic control rolling mill is studied.Through the analysis of the rolling deformation zone,the deformation zone composition form of a large diameter ratio roll system and a calculation formula of neutral angle under tension are proposed.To analyze the effect of front and post tensions on the rolling characteristic and the strip flatness control characteristic,a three-dimensional rolling finite element(FE)model of a large diameter ratio roll system with the function of roll profile electromagnetic control is established by FE software and verified by a strip flatness electromagnetic control rolling mill.Based on the model,the strip thickness characteristic,metal transverse flow,strip flatness state,and adjustment range of the loaded roll gap are analyzed for different front and post tensions setting values.The results show that changing the front or post tension setting values can improve the single-pass reduction rate of a large diameter ratio roll system and have little effect on the flatness control ability of the strip flatness electromagnetic control rolling mill.展开更多
基金Sponsored by National Natural Science Foundation of China(50175095)Provincial Natural Science Foundation of Hebei of China(502173)
文摘A new method,the stream surface strip element method,for simulating the three-dimensional deformation of plate and strip rolling process was proposed.The rolling deformation zone was divided into a number of stream surface(curved surface)strip elements along metal flow traces,and the stream surface strip elements were mapped into the corresponding plane strip elements for analysis and computation.The longitudinal distributions of the lateral displacement and the altitudinal displacement of metal were respectively constructed to be a quartic curve and a quadratic curve,of which the lateral distributions were expressed as the third-power spline function,and the altitudinal distributions were fitted in the quadratic curve.From the flow theory of plastic mechanics,the mathematical models of the three-dimensional deformations and stresses of the deformation zone were constructed.Compared with the streamline strip element method proposed by the first author of this paper,the stream surface strip element method takes into account the uneven distributions of stresses and deformations along altitudinal direction,and realizes the precise three-dimensional analysis and computation.The simulation example of continuous hot rolled strip indicates that the method and the model accord with facts and provide a new reliable engineering-computation method for the three-dimensional mechanics simulation of plate and strip rolling process.
基金supported by the Program for Changjiang Scholars and Innovative Research Team in University (Grant No. IRT0713)
文摘The paper investigated the texture evolution of a biomedical β-titanium alloy (Ti-28Nb-13Zr-2Fe) under 15%-85% cold rolling reduction and 700°C-900°C recrystallization annealing treatment,and clarified the effects of crystal orientation on Young’s modulus of the alloy.Orientation distribution function (ODF) maps and electron backscatter diffraction (EBSD) analysis revealed that the rolling texture type changed with the increase of reduction according to the sequence:α-fiber texture→γ-fiber texture→α-rotated cubic texture.Young’s modulus exhibited the lowest value 54 GPa under 15% reduction.Strong {111}【112】 γ-fiber texture was developed after rolling 85% reduction and annealing at 700°C,which was favorable to decreasing Young’s modulus in comparison with randomly orientated microstructure.Cyclic loading-unloading tensile test proved that the gradual rotation of {110} slip plane during plastic deformation promoted the development of {001}【110】 texture component,leading to the marked decrease of Young’s modulus.
基金supported by the Natural Science Foundation of Hebei Province of China(Grant No.E2021203129).
文摘To achieve stable rolling,the influence of a tension mechanism of a large diameter ratio roll system on the rolling process of a strip flatness electromagnetic control rolling mill is studied.Through the analysis of the rolling deformation zone,the deformation zone composition form of a large diameter ratio roll system and a calculation formula of neutral angle under tension are proposed.To analyze the effect of front and post tensions on the rolling characteristic and the strip flatness control characteristic,a three-dimensional rolling finite element(FE)model of a large diameter ratio roll system with the function of roll profile electromagnetic control is established by FE software and verified by a strip flatness electromagnetic control rolling mill.Based on the model,the strip thickness characteristic,metal transverse flow,strip flatness state,and adjustment range of the loaded roll gap are analyzed for different front and post tensions setting values.The results show that changing the front or post tension setting values can improve the single-pass reduction rate of a large diameter ratio roll system and have little effect on the flatness control ability of the strip flatness electromagnetic control rolling mill.
