Continuous steel casting process and device with function of electromagnetic excitation compound mechanical stirring

Abstract

The invention discloses a continuous steel casting process with a function of electromagnetic excitation compound mechanical stirring. According to the process, when alloy melt solidifies, microscopic and macroscopic strong shear flows are generated to break dendritic crystal by the electromagnetic excitation compound mechanical stirring technology, and accordingly, solidification structure refinement, full-equiaxed crystallization and solute segregation reduction are achieved, and alloy properties are improved. The invention further provides a continuous steel casting device mainly comprising a crystallizer, a rotor stirring paddle, a wheel, a program control motor, a magnetic field generator, a coil, and a voltage-regulating frequency-modulating alternating current source. The microscopic flows generated by electromagnetic excitation and macroscopic flows generated by mechanical stirring form complex chaotic flows which form strong shear flows to brake the dendritic crystal, crystal nucleus proliferation is prompted, temperature gradient is reduced, and ultrafine full-equiaxed crystal structure is achieved; meanwhile, segregation of alloy elements is significantly reduced or completely suppressed. The continuous steel casting process and method has the advantages that the energy consumption is significantly lower than that of conventional electromagnetic stirring and energy conservation is significantly effective.

Description

technical field [0001] The invention relates to a metal continuous casting process and a metal continuous casting device, in particular to a metal continuous casting process and a metal continuous casting device for enhancing stirring of a metal melt, and is applied in the technical field of solidification. Background technique [0002] Due to its comprehensive properties such as good anti-stiction, wear resistance and friction reduction, corrosion resistance, compliance and embedding, it also has the advantages of low density, good thermal conductivity, large bearing capacity and high fatigue strength. Bearing alloys are increasingly used to replace traditional tin bronze and babbitt alloys, and become the preferred material for bearings in automotive diesel engines to meet the requirements of high speed, heavy load, energy saving and emission reduction. However, the aluminum-tin bearing alloy prepared by the traditional water-cooled iron mold casting method has coarse grai...

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Problems solved by technology

Powder metallurgy technology can be used to prepare aluminum-tin alloys with relatively uniform components, but the process is complicated, the powder surface is easy to oxidize, and the mechanical properties and density of the alloy are poor; Macro-segregation and low-oxygen blanks, but the cost is very high and the production efficiency is relatively low; using rapid solidification technology, it is possible to prepare aluminum-tin alloy solidification structures with very fine grains, but for large-sized, complex-shaped blanks As far as castings are concerned, the actual effect of this technology is not good, and the cost of industrial application is high; using pulsed magnetic field technology and electromagnetic stirring technology, the aluminum-tin alloy melt is stirred without contact, and the uniform temperature field can be achieved to a certain extent. Refining the solidification structure and reducing the degree of segregation, however, both of these technologies are produced by alternating magnetic fields, and when the alternating magnetic field passes through the copper crystallizer, the huge shielding effect will cause huge energy loss. Even if the alternating magnetic field passes through the mold, there is still a skin effect in the aluminum-tin alloy melt, which will further weaken the effect of electromagnetic force. Therefore, the grain refinement effect of the slab is not obvious, and the area where the electromagnetic force acts is limited

It can be seen that there is still a lack of effective means to control the grain size and solute segregation of the solidification structure of aluminum-tin alloys.

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