Process and device for refining solidified microstructure by consumable shear flow method

Abstract

The invention discloses a technology for refining a solidification structure through a consumable shear flow method. The technology for refining the solidification structure through the consumable shear flow method is a melt processing method which increases the number of crystal nucleus, refines grains and uniformizes formations through a consumable shear flow, and used for the casting process of large ingot castings and continuous casting billets in large cross section sizes. During the solidification of metal bath, a high-speed motor is used for generating a high rotation speed, a strong shear flow is generated in a tiny gap between a consumable metal rotor component and a consumable metal stator component, the consumable metal rotor component and the consumable metal stator component efficiently generate a plurality of crystal nucleuses under the condition that liquid level stability is not affected in a controllable space, and 'crystal rain' effect is generated. In addition, stator consumable metal and rotor consumable metal move downwards under the drive of a screw, the consumable metal can be supplemented, the purposes of improving solidification speed, refining grains, increasing equiaxial crystal ratio and reducing solute segregation degree are ultimately achieved, and the alloy performance is improved. The invention further provides a consumable shear flow metal melt processing device. The consumable shear flow metal melt processing device comprises a shear consumable component fixing device, a shear consumable component driving device and shear consumable components made of consumable metal.

Description

technical field [0001] The invention relates to a process and device for treating molten metal, in particular to a process and device for increasing the number of crystal nuclei by shear self-consumption and stirring the molten metal within a controllable range, which is applied to metal solidification technology field. Background technique [0002] In machinery manufacturing, cast steel is widely used. In recent years, with the rapid development of modern industrial technology, large-scale is the development trend of modern forging production. To obtain large-scale forgings with good quality, high strength and large size, it is necessary to provide large-scale steel ingots with good quality. Therefore, the development of steel ingots also follows the trend of large-scale development, and the quality requirements are getting higher and higher. For example, the low-voltage rotor of a nuclear power plant with a power of 1300MW needs to be manufactured with a giant steel ingo...

AI Technical Summary

Problems solved by technology

These methods solve the above problems to a certain extent, but there are more or less unavoidable defects

When the refiner of dissimilar materials is added, it is necessary to strictly control the amount of refiner added in order to achieve a better refinement effect, and in some fields that require high metal purity, the addition of refiner of dissimilar materials will also cause metal At present, it is also possible to see the method of increasing the number of crystal nuclei in the solidification system by adding the same metal in the shape of filaments, ribbons, cakes or rods, but because the added metal is prone to inhomogeneous melting, the newly formed crystal nuclei The problem of uneven distribution limits the application of this method; electromagnetic stirring has the advantage of not directly contacting the solidified metal, avoiding the pollution of the solidified metal, but there is a problem of attenuation of electromagnetic stirring, with the ingot or continuous casting The size of the billet section increases, and the effect of electromagnetic stirring is greatly reduced

As for the steel ingot mold used for large steel ingot, because it is magnetic and the wall thickness is very thick, even if a very low frequency or even DC magnetic field is used at the same time as a high-power electromagnetic generator, the electromagnetic field can hardly penetrate into the molten steel in the steel ingot mold, resulting in Electromagnetic stirring has no effect, and the high energy consumption of electromagnetic stirring devices is still a problem that needs to be solved urgently; similarly, ultrasonic stirring also has problems such as serious attenuation, and the reaction between the probe and molten steel or alloy liquid. It will be corroded by the metal melt, resulting in a short service life of the agitator. At the same time, the corrosion of the agitator will also cause metal pollution. Improper stirring speed will also cause hazards such as slag rolling.

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