1.1 This specification covers the detailed requirements to which flat-rolled thin-gauge nonoriented fully processed electrical steel shall conform. Nominal thicknesses included in this specification are 0.004 to 0.012 in. (0.10 to 0.30 mm). 1.1.1 Refer to Specification A677 for properties of flat-rolled nonoriented fully processed electrical steel in nominal thicknesses of 0.014 to 0.025 in.(0.36 to 0.64 mm). 1.1.2 Refer to Specification A876 for properties of flat-rolled grain-oriented fully processed electrical steel. 1.1.3 Thin-gauge nonoriented electrical steels with a high silicon content (typically 6 1/2 %) manufactured using silicon vapor-deposition or similar processes are not included in this specification. 1.2 The steel covered in this specification is produced to specified maximum core-loss values and is intended primarily for use in rotating electrical machinery and other electromagnetic devices operating at moderate to elevated frequencies (100 Hz and greater). Desirable core-loss and permeability characteristics are developed during mill processing; however, lamination manufacturing processes may adversely affect these mill-produced properties; additional stress-relief heat treatment by the user may therefore be helpful in remediating these properties in the manufactured laminations. Stress-relief annealing is discussed further in Appendix X2. 1.3 These thin-gauge nonoriented fully processed electrical steels are low-carbon, silicon-iron, or silicon-aluminum-iron alloys typically containing 2.5 to 3.5 % silicon and a small amount of aluminum. 1.4 The values stated in customary (cgs-emu and inch pound) units are to be regarded as the standard. The values given in parentheses are mathematical conversions to SI units which are provided for information only and are not considered standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
Since the deactivation of MIL-S-46084 in 1978, there has been no controlling U.S. standard for these materials. In recent years, there has been increased design activity with these materials across many industries and the user community has expressed a growing interest in a standard for thin silicon steels. While these materials could be included in a revision of Specification A677, currently under review, the expected differences in testing conditions and resulting changes in nomenclature warrant the investigation of this as a new standard. Expected users will be involved in the design, manufacture, and testing of rotating electrical machinery operating at elevated frequencies and may include U.S. governmental agencies and their subcontractors, commercial manufacturers of electrical machines, U.S. National Laboratories, academic institutions, and corporate research centers.
Keywordscore loss; thin-gauge electrical steel; electrical steel; flat-rolled; fully processed; nonoriented, silicon steel
The title and scope are in draft form and are under development within this ASTM Committee.Back to Top
Ballot Item Approved as A1086-2013 and Pending Publication