ASTM A726 - 18

    Standard Specification for Cold-Rolled Magnetic Lamination Quality Steel, Semiprocessed Types

    Active Standard ASTM A726 | Developed by Subcommittee: A06.02

    Book of Standards Volume: 03.07


      Format Pages Price  
    PDF 7 $48.00   ADD TO CART
    Hardcopy (shipping and handling) 7 $48.00   ADD TO CART
    Standard + Redline PDF Bundle 14 $58.00   ADD TO CART



    Abstract

    This specification covers the standard requirements for cold-rolled magnetic lamination quality steel that can be used for magnetic applications. The steels shall be made by the basic-oxygen or electric-furnace method and shall be processed by hot rolling, pickling, cold rolling, annealing, and temper rolling. Magnetic lamination steels shall have low-carbon contents and may have manganese, phosphorus, silicon, and aluminum additions to enhance punchability and to improve magnetic characteristics by increasing the electrical resistivity. A test method for alternating-current magnetic properties shall be performed, and shall conform to the limits of core loss and permeability values. The magnetic properties of these steels shall be optimized by annealing of the stamped laminations or assembled core structures. Materials shall also undergo mechanical tests to determine steel hardness which is dependent on chemical composition and mill processing. Finished products shall be marked by having the producer’s order number and material identification legibly shown on a tag attached to each coil or shipping unit.

    This abstract is a brief summary of the referenced standard. It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use and application. ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date.

    1. Scope

    1.1 This specification covers cold-rolled carbon sheet steel used for magnetic applications. These products, commonly called “cold-rolled magnetic lamination steel” (CRML) are usually intended for applications in which the stamped laminations or assembled core structures for electrical equipment are annealed to develop the desired core loss and permeability characteristics.

    1.2 This steel is produced to maximum specific core-loss values and is intended primarily for commercial power frequency (50- and 60-Hz) applications in magnetic devices. Specific core-loss and permeability characteristics in conformance with this specification are developed through heat treatment by the user.

    1.3 Non-guaranteed core-loss types, usually made to controlled chemical compositions, are available but are not covered by this specification.

    1.4 Higher quality core-loss types are low carbon, silicon-iron, or silicon-aluminum-iron alloys containing up to about 2.5 % silicon and less than 1 % aluminum. These steels are usually given a critical reduction on a temper-mill to yield specified magnetic properties after a suitable lamination anneal. These products, typically called semiprocessed magnetic lamination steel, are classified by the ASTM Code Letter D in accordance with Practice A664.

    1.5 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to customary (cgs-emu and inch-pound) units which are provided for information only and are not considered standard.

    1.6 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

    1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.


    2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

    ASTM Standards

    A34/A34M Practice for Sampling and Procurement Testing of Magnetic Materials

    A340 Terminology of Symbols and Definitions Relating to Magnetic Testing

    A343/A343M Test Method for Alternating-Current Magnetic Properties of Materials at Power Frequencies Using Wattmeter-Ammeter-Voltmeter Method and 25-cm Epstein Test Frame

    A370 Test Methods and Definitions for Mechanical Testing of Steel Products

    A664 Practice for Identification of Standard Electrical Steel Grades in ASTM Specifications

    A700 Guide for Packaging, Marking, and Loading Methods for Steel Products for Shipment

    A717/A717M Test Method for Surface Insulation Resistivity of Single-Strip Specimens

    A937/A937M Test Method for Determining Interlaminar Resistance of Insulating Coatings Using Two Adjacent Test Surfaces

    A976 Classification of Insulating Coatings for Electrical Steels by Composition, Relative Insulating Ability and Application

    E18 Test Methods for Rockwell Hardness of Metallic Materials

    E140 Hardness Conversion Tables for Metals Relationship Among Brinell Hardness, Vickers Hardness, Rockwell Hardness, Superficial Hardness, Knoop Hardness, Scleroscope Hardness, and Leeb Hardness


    ICS Code

    ICS Number Code 77.140.40 (Steels with special magnetic properties)

    UNSPSC Code

    UNSPSC Code 31380000(Magnets and magnetic materials)


    Referencing This Standard
    Link Here
    Link to Active (This link will always route to the current Active version of the standard.)

    DOI: 10.1520/A0726-18

    Citation Format

    ASTM A726-18, Standard Specification for Cold-Rolled Magnetic Lamination Quality Steel, Semiprocessed Types, ASTM International, West Conshohocken, PA, 2018, www.astm.org

    Back to Top