Electrical steel processing without a post cold-rolling intermediate anneal

Abstract

Embodiments of the present invention comprise; annealing steel sheets (e.g., hot rolled steel sheets or thin cast strip steel); cold rolling the sheets in one or more cold rolling steps (e.g., with annealing steps between multiple cold rolling steps); and performing one or more of tension leveling, a rough rolling, or a coating process on the sheets after cold rolling, without an intermediate annealing step between the final cold rolling step and the tension leveling, the rough rolling, or the coating process, or the customer stamping or final customer annealing. In order to achieve the desired properties for the steel sheet, stamping and final annealing is performed by the customer. The new process provides an electrical steel with the similar, same, or better magnetic properties than an electrical steel manufactured using the traditional processing that utilizes an intermediate annealing step after cold rolling and before the stamping and final annealing.

Description

RELATED APPLICATIONS AND PRIORITY CLAIM[0001]This application is a continuation-in-part of, and claims priority to U.S. patent application Ser. No. 14 / 334,239 entitled “Electrical Steel Processing Without A Post-Cold Rolling Intermediate Anneal,” filed on Jul. 17, 2014, which is a continuation-in-part application, and claims priority to U.S. patent application Ser. No. 13 / 739,184 entitled “Electrical Steel Processing Without A Post-Cold Rolling Intermediate Anneal,” filed on Jan. 11, 2013, which claims priority to Provisional Application No. 61 / 586,010 filed Jan. 12, 2012, and which are all assigned to the assignee hereof and hereby expressly incorporated by reference herein.BACKGROUND[0002]This invention relates generally to the field of semi-processed electrical steel sheet manufacturing, and more particularly embodiments of the invention relate to achieving electrical steel sheet products with the desired final magnetic properties after they have been annealed at the customer. Se...

AI Technical Summary

Benefits of technology

The patent describes a method for processing electrical steel to improve its magnetic properties. The method involves hot rolling, pickling, annealing, and cold rolling steps to control the grain structure and strength of the steel. Unlike traditional methods, the present invention does not require an intermediate annealing step after cold rolling. Instead, a tension leveling step or coating may be applied to the semi-processed electrical steel sheet before it is sent to the customer. The customer then performs a customer annealing step to remove distortions and maximize the magnetic properties of the electrical steel. The technical effects of the invention include higher permeability and low core loss, which result in higher efficiency of the final product.

Problems solved by technology

The core loss is the energy wasted in the electrical steel.

Improving one property may come at the detriment of another.

For example, when increasing the permeability a higher core loss may result (and vice versa).

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