Induction heating nitriding method for oriented silicon steel

Abstract

Disclosed is an induction heating nitriding method for oriented silicon steel. The method comprises the steps that smelting and continuous casting are carried out, then a casting blank is heated, andthen subjected to hot rolling, normalizing, cold rolling and decarburization; and in an induction nitriding furnace, two stages of nitriding treatment are carried out: natural cooling to room temperature under dry N2 atmosphere, applying isolating agent, and high temperature purification annealing for standby use. Nitrides obtained by the nitriding method are numerous and evenly distributed, and the depth of a nitriding layer can reach the central part of the steel plate thickness, AlN particles on the central part of the steel plate thickness reach 1-1.5 per square micron, and the final magnetic performance is stable, and the deviation is small, that is, the fluctuation between batches does not exceed 0.02 T; at the same time, the consumption of ammonia gas is reduced by not less than 40%, and the operation is simple, the implementation is easy, and mass production is easy to realize.

Description

technical field [0001] The invention relates to a nitriding method for high magnetic induction oriented silicon steel, and is particularly suitable for an induction nitriding method for producing slab low-temperature heating oriented silicon steel with AlN as inhibitor. Background technique [0002] In order to obtain excellent magnetization properties, slab low-temperature heating oriented silicon steel with AlN as the main inhibitor in the production process needs to be gas nitriding process with ammonia gas after the cold rolling decarburization process and before the high temperature annealing process. Ammonia nitriding is a surface adsorption and diffusion process. Ammonia gas is active in nature. When it enters the nitriding furnace, it is thermally decomposed or decomposed into active [N] and [H]. Crystalline structure, so that good grain orientation can be obtained after secondary recrystallization, so as to achieve the purpose of nitriding. [0003] At present, ma...

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Problems solved by technology

However, in the case of continuous operation of the steel strip, the plasma nitriding method needs to be carried out under a specific vacuum degree, which requires high equipment and production operations, which is not conducive to the promotion of oriented silicon steel manufacturing enterprises.

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