Non-Oriented Electrical Steel Having High Magnetic Induction And High Intensity And Manufacturing Method Thereof

Abstract

A non-oriented electrical steel has relative high magnetic induction and high intensity without increasing manufacturing difficulty. The weight percentage of the compositions of the electrical steel are as follows: C≦0.0040%, Si is 2.50% to 4.00%, Al is 0.20% to 0.80%, Cr is 1.0 to 8.0%, Ni is 0.5 to 5.0%, Mn≦0.50%, P≦0.30%, S≦0.0020%, N≦0.0030%, Ti≦0.0030%, Nb≦0.010%, V≦0.010%, C+S+N+Ti≦0.010%, and a balance substantially being Fe and inevitable impurities.

Description

[0001]The present application is a continuation of PCT Patent Application No. PCT / CN2011 / 073368 filed on Apr. 27, 2011, which claims priority to Chinese Patent Application No. 201010518005.5 filed on Oct. 25, 2010, both of which are fully incorporated herein by reference.STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT[0002]Not applicable.TECHNICAL FIELD[0003]The present invention relates to manufacturing of an electrical steel field, especially to a non-oriented electrical steel having relative high magnetic induction and high intensity and a manufacturing method thereof, which is applied in devices requiring high starting torque and impact resistant performance, such as electric automobile motor and running-up electric machine, wherein by adding solid molten strengthening elements such as Ni, Cr and the like, as well as controlling elements that damage magnetic property such as C, N, S, Ti and the like, the magnetic property of the electrical steel may be ensured so...

AI Technical Summary

Benefits of technology

The present invention provides a non-oriented electrical steel with high magnetic induction and high intensity, which can be manufactured without increasing manufacturing difficulty. The technical solution involves a specific chemical composition and a manufacturing process involving smelting, hot rolling, hot rolling normalizing, acid pickling, cold rolling, annealing with continuous furnace, and other steps. The non-oriented electrical steel has a weight percentage of chemical compositions as follows: C≦0.004%, Si is 2.8 to 4.4%, Al is 0.2 to 0.8%，Cr is 1.0 to 8.0%，Ni is 0.5 to 5.0%，Mn is 0.1 to 0.5%，P is 0.0 to 0.3%，S is 0.0 to 0.20%，N is 0.0 to 0.30%，Ti is 0.0 to 0.30%，Nb is 0 to 5.0%，V is 0 to 0.20%，C+S+N+Ti≦0.0 to 0.1%, and a balance of Fe and inevitable impurities. The non-oriented electrical steel can be manufactured without increasing manufacturing difficulty and has high magnetic induction and high intensity.

Problems solved by technology

Also, rotor cores of motor endures extreme strain due to centrifugal force in a high speed, and is subjected to strong impact momentarily when automobile starts up, so it is required for core material to possess high intensity and toughness.

But toughness and plasticity of this kind of products is bad, being prone to creak, and magnetic induction is relatively low as well, which is not applied in the use of running-up electric machine such as electric automobile motor, so it is necessary to develop a non-oriented electrical steel having high intensity and high magnetic induction.

In order to improve the intensity of the product, it is necessary to cool from high temperature to intermediate temperature at a high cooling speed after the cold rolling plate is annealed, but in this treatment, a larger stress will be produced in the inner of the strip which has a bad influence on the shape of the strip, and affects the magnetic property and fatigue resistance of the product.

Also, in this patent application, it is necessary to hold a long time at intermediate temperature zone to carry out hardening treatment in annealing and cooling for cold rolling, which is adverse to achieve in a normal industrial annealing machine set.

But in this method, intense stress will be produced in strip, having a strong influence on the shape of the strip and the magnetic property, which is adverse to be applied in actual industrial production.