JWG 1 - TC 68/JWG 1

IEC 60404-8-11:2018 defines the grades of Fe-based amorphous strip delivered in the semi‑processed state, i.e. without final heat treatment, of nominal thickness 0,025 mm. Other nominal thicknesses in the range from 0,020 mm to 0,030 mm can be specified by agreement between the manufacturer and the purchaser at the time of enquiry and order. In particular, it gives general requirements, magnetic properties, geometric characteristics, tolerances and technological characteristics, as well as inspection procedures.
This document applies to the rapidly-solidified Fe-based amorphous strip supplied in coils with as-cast edges and intended for the construction of magnetic circuits.
The grades are grouped into two classes:
- conventional grades;
- high permeability grades.
They correspond to Class I1 of IEC 60404-1.

IEC 60404-8-8:2017(E) defines the grades of thin non-oriented electrical steel strip and sheet in nominal thicknesses of 0,05 mm, 0,10 mm, 0,15 mm, 0,20 mm, 0,25 mm, 0,30 mm and 0,35 mm and of thin grain-oriented electrical steel strip and sheet in nominal thicknesses of 0,05 mm, 0,10 mm, 0,15 mm and 0,18 mm. In particular, it gives general requirements, magnetic properties, geometric characteristics and tolerances, technological characteristics, as well as inspection procedures.
NOTE For thin non-oriented electrical steel strip and sheet, other nominal thicknesses (i.e. 0,12 mm, 0,18 mm, 0,23 mm and 0,27 mm) can be agreed between the manufacturer and the purchaser.
This document applies to electrical steel strip and sheet supplied in the finally annealed condition in coils or sheets and intended for the construction of magnetic circuits predominantly used at frequencies in the range from 100 Hz to 10 kHz.
This edition includes the following significant technical changes with respect to the previous edition:
- extension of the range of electrical steels to include the improved grades.

IEC 60404-8-7:2017 is available as IEC 60404-8-7:2017 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.
IEC 60404-8-7:2017 defines the grades of cold-rolled grain-oriented electrical steel strip and sheet in nominal thicknesses of 0,23 mm, 0,27 mm, 0,30 mm and 0,35 mm. In particular, it gives general requirements, magnetic properties, geometric characteristics, tolerances and technological characteristics, as well as inspection procedures. This document applies to Goss textured grain-oriented electrical steel strip and sheet supplied in the final annealed condition in coils or sheets, and intended for the construction of magnetic circuits.
The grades are grouped into two classes:
– conventional grades;
– high permeability grades, including grades which may be delivered in the domain refined condition. They correspond to Class C22 of IEC 60404-1.
This fourth edition cancels and replaces the third edition published in 2008. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
– extension of the range of electrical steels to include the improved grades.

IEC TR 62981:2017(E), which is a Technical Report, provides the results of international exercises and comparisons focusing on achieving the knowledge of the statistical performance of single sheet tester (SST) measurements made on grain-oriented electrical steel. These experiments aim at specifying obligatory reference values, measured by the single sheet test method, for the grading of high permeability (P grades) grain-oriented (g.-o.) materials, independently from the Epstein classification as it is practiced today. Besides this, Epstein test measurements have been made in order to gain more up-to-date statistical performance for comparison with the SST statistical characteristics. A few experiments were carried out aiming at improved knowledge on the systematic error performance of the SST, i.e. they were to determine the correlation between the quality of insulation separating laminations in the SST yokes and the measured loss.

IEC 60404-8-4:2013 defines the grades of cold-rolled non-oriented electrical steel strip and sheet in nominal thicknesses of 0,35 mm, 0,50 mm, 0,65 mm and 1,00 mm. It specifies general requirements, the magnetic properties, geometric characteristics and tolerances, and technological characteristics, as well as the inspection procedure. This standard applies to materials supplied in the fully annealed condition intended for the construction of magnetic circuits. It does not apply to semi-processed material. This edition includes the following significant technical changes with respect to the previous edition:
- Deletion of the dates for all normative references;
- Introduction of the new grades M210-35A 5 and M230-50A 5.

IEC 60404-8-10:2009 specifies the general requirements, magnetic properties, geometric characteristics and tolerances as well as inspection procedures for magnetic materials used primarily for relays. This standard applies to pure iron, non-alloyed and alloyed steel and ferritic stainless steel products usually delivered in either the semi-processed or fully-processed state. These materials correspond to classes A, B, C and D.3 of IEC 60404-1. This second edition cancels and replaces the first edition published in 1994 and constitutes a technical revision. The main modifications from the previous edition of the standard are as follows:
- introduction of the ferritic stainless steels and the fully-processed state in the scope of the standard (see Clause 1);
- modification of the designation with the letter R at the beginning and the condition and state at the end (see Clause 5);
- introduction of the new grades R160 and R320 (see Table 2);
- modification of the requirements for the heat treatment of test specimens for semi-processed material (see Subclause 8.3.1);
- indication in Bibliography of standards referred to in this standard as an information.