This part of IEC 404 specifies the methods used for determining the density, resistivity and stacking factor of electrical steel sheet and strip. These quantities are necessary to establish the magnetic characteristics of the material. In particular, the density is necessary to allow specified values of the flux density to be set without knowing the thick-ness of the test specimen.
For the determination of the density, the immersion method was earlier considered to be a fundamental method for use in cases of arbitration. However, experience has shown that this method is very difficult to use in the case of sheet samples with a relatively large surface area. This method is therefore not included. It is described in ISO 2738 and ISO 1183.