Preparation method of rare earth ferroalloy

Abstract

The invention discloses a preparation method of a rare earth ferroalloy. The preparation method of the rare earth ferroalloy comprises the steps that a rare earth iron immediate alloy is prepared by non-self-consuming cathode electrolysis; an electrolyte is loaded in an electrolytic cell, a graphite carbon plate is used as an anode, a tungsten or molybdenum material is used as an cathode, and a crucible under the tungsten and molybdenum cathode is used as a receiver; in an electrolyte system of rare earth fluoride and lithium fluoride molten salt, rare earth oxide and iron are used as raw materials, then a direct current is passed for electrolysis, and the rare earth iron immediate alloy is obtained in the receiver; and the rare earth iron immediate alloy and iron are put into the crucibleas the raw materials, and the rare earth iron immediate alloy is further smelted by a melting and mixing method in a medium frequency induction furnace to obtain the rare earth ferroalloy. The rare earth ferroalloy obtained by the preparation method has uniform and stable composition, low impurity element content and close density and melting point to the density and melting point of steel, and the rare earth ferroalloy is easy to be added to the steel; and the rare earth ferroalloy can fundamentally solve the problem of effective addition of rare earth in the steel and can accurately controlthe content of the rare earth in the steel.

Description

technical field [0001] The invention relates to a production technology of a rare earth iron alloy, in particular to a preparation method of a rare earth iron alloy using a dual method of non-consumable cathode electrolysis and intermediate frequency furnace component regulation. Background technique [0002] At present, steel is the largest metal structural material and is widely used in construction, energy, transportation, aerospace and other fields. The application and research of rare earths in steel have also developed rapidly. The addition of rare earths to molten steel can desulfurize, deoxidize, change the shape of inclusions, etc., and can improve the plasticity, stamping performance, wear resistance and welding performance of steel. Various rare earth steels such as rare earth steel plates for automobiles, die steels, rails, etc. have been widely used. [0003] The addition method of rare earth in the production process of rare earth steel has always been the foc...

AI Technical Summary

Problems solved by technology

This method is the method commonly used at present, and its process technology is simple, can make multi-element master alloy or application alloy, but also has deficiency: 1) rare earth metal easily local concentration is too high in molten iron, produces segregation; 2) this method The raw materials used are rare earth metals, especially for medium and heavy rare earth metals, the preparation process is complicated and the cost is high; 3) The melting temperature is relatively high. Since rare earth metals and pure iron are used as raw materials, the melting temperature requirements are high

This method has low production cost and simple process, but it also has the following defects: the distribution of rare earth and iron in the alloy fluctuates greatly, it is difficult to control, and the distribution error is as high as 3%-5%, which affects product consistency

[0009] However, the oxygen content in the rare earth iron alloy prepared by the miscibility method and molten salt electrolysis method is relatively high. After being added to the ladle, the generated inclusions are likely to cause nozzle blockage, which affects normal tapping.

Precise control of rare earth elements cannot be achieved when preparing rare earth ferroalloys by miscible method and molten salt electrolysis

The currently used crucible will still bring in impurities when smelting rare earth metals and their alloys

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