than 2.2, the electromagnetic pressure acting on melt can be simply expressed as Pm =B^2/wμ, and the melt shape would be known only by measuring the distribution of magnetic flux density. As a is small and makes the ...than 2.2, the electromagnetic pressure acting on melt can be simply expressed as Pm =B^2/wμ, and the melt shape would be known only by measuring the distribution of magnetic flux density. As a is small and makes the ratio a/8 less than 2.2, the melt shape and electromagnetic pressure for confining and shaping are determined not only by magnetic flux density B but also by melt thickness a, electromagnetic parameter μγ and current frequency f. In this paper, an equation used to calculate electromagnetic pressure acting on 'thin plate-form melt' is brought forward. The equation gives a precise relationship between electromagnetic pressure factor p and melt thickness a, electromagnetic parameter μγ and current frequency f.展开更多
Dual frequency electromagnetic confinement and shaping (EMCS) makes it easier to adjust and control the shaping temperature field and magnetic field than single frequency EMCS. The shaping stability and temperature fi...Dual frequency electromagnetic confinement and shaping (EMCS) makes it easier to adjust and control the shaping temperature field and magnetic field than single frequency EMCS. The shaping stability and temperature field of the dual frequency EMCS were investigated. The results indicate that to shape stably, the upper liquid/solid interface should be in appropriate position and the lower liquid/solid interface must be above the critical position. The current of heating induction coil and the drawing speed of sample affect the shaping temperature and its peak position, while the current of the shaping induction coil only influences the shaping temperature. During EMCS, the speed of shaped sample affects not the height of the molten metal, but the temperature of molten metal. The height of the molten metal for steady shaping was about 15 mm in the experimental conditions. Several stainless steel plate-like parts with high width to thickness ratio (≥3.5) and directional structure were obtained.展开更多
The 3-dimension numerical simulation study on the electromagnetic dam used in the twin roll caster has been performed by using the edge element method. It was found that the materials and structures of the roll collar...The 3-dimension numerical simulation study on the electromagnetic dam used in the twin roll caster has been performed by using the edge element method. It was found that the materials and structures of the roll collars have great influence on the distribution of the magnetic flux density, eddy current density and the electromagnetic force in the molten pool. The conductive collars make the magnetic flux density decreased in the molten pool, but it also makes the magnetic force more uniformly, and the force in the low part of the molten pool where needs greater force have increased some what. The conductive collars make the EMD device more effective than the nonconductive collars.展开更多
The purpose of this work is to investigate theoretically the characteristics of confined electromagnetic modes propagating along the interfaces of a multilayer device.This one dimensional(1D)sensor is formed by stacki...The purpose of this work is to investigate theoretically the characteristics of confined electromagnetic modes propagating along the interfaces of a multilayer device.This one dimensional(1D)sensor is formed by stacking a left-handed material(LHM)layer between a SiO2-glass prism and a dielectric gap layer in contact with gold(Au).The results indicate that the total thickness of the LHM layer and dielectric gap,in optimum conditions,give the ability of tuning significantly the characteristics of the resonant modes correlated to surface plasmons(SPs)propagation along the interfaces of the designed device.By considering two arrangements between LHM and Au,two opposite resonant behaviors observed in p-reflectance spectra are analyzed in the angular interrogation mode and discussed thoroughly.展开更多
基金National Natural Science Foundation! No. 59995440National PostDoctor Science Foundation !([19971 11)of China
文摘than 2.2, the electromagnetic pressure acting on melt can be simply expressed as Pm =B^2/wμ, and the melt shape would be known only by measuring the distribution of magnetic flux density. As a is small and makes the ratio a/8 less than 2.2, the melt shape and electromagnetic pressure for confining and shaping are determined not only by magnetic flux density B but also by melt thickness a, electromagnetic parameter μγ and current frequency f. In this paper, an equation used to calculate electromagnetic pressure acting on 'thin plate-form melt' is brought forward. The equation gives a precise relationship between electromagnetic pressure factor p and melt thickness a, electromagnetic parameter μγ and current frequency f.
文摘Dual frequency electromagnetic confinement and shaping (EMCS) makes it easier to adjust and control the shaping temperature field and magnetic field than single frequency EMCS. The shaping stability and temperature field of the dual frequency EMCS were investigated. The results indicate that to shape stably, the upper liquid/solid interface should be in appropriate position and the lower liquid/solid interface must be above the critical position. The current of heating induction coil and the drawing speed of sample affect the shaping temperature and its peak position, while the current of the shaping induction coil only influences the shaping temperature. During EMCS, the speed of shaped sample affects not the height of the molten metal, but the temperature of molten metal. The height of the molten metal for steady shaping was about 15 mm in the experimental conditions. Several stainless steel plate-like parts with high width to thickness ratio (≥3.5) and directional structure were obtained.
基金This study was financially supported by the National Natural Science Foundation of China under the Grant No.59995440 and the Natural Science Foundation of Liaoning Province under the Grant No.2001101021.
文摘The 3-dimension numerical simulation study on the electromagnetic dam used in the twin roll caster has been performed by using the edge element method. It was found that the materials and structures of the roll collars have great influence on the distribution of the magnetic flux density, eddy current density and the electromagnetic force in the molten pool. The conductive collars make the magnetic flux density decreased in the molten pool, but it also makes the magnetic force more uniformly, and the force in the low part of the molten pool where needs greater force have increased some what. The conductive collars make the EMD device more effective than the nonconductive collars.
文摘The purpose of this work is to investigate theoretically the characteristics of confined electromagnetic modes propagating along the interfaces of a multilayer device.This one dimensional(1D)sensor is formed by stacking a left-handed material(LHM)layer between a SiO2-glass prism and a dielectric gap layer in contact with gold(Au).The results indicate that the total thickness of the LHM layer and dielectric gap,in optimum conditions,give the ability of tuning significantly the characteristics of the resonant modes correlated to surface plasmons(SPs)propagation along the interfaces of the designed device.By considering two arrangements between LHM and Au,two opposite resonant behaviors observed in p-reflectance spectra are analyzed in the angular interrogation mode and discussed thoroughly.
