ASTM A753-97 - 10.10.1997
 
1. Scope

1.1 This specification covers commonly used wrought nickel-iron soft magnetic alloys produced or supplied expressly for use in magnetic cores and other parts requiring high magnetic permeability, high electrical resistivity, low coercive force, and low core loss.

1.2 This specification covers materials supplied by a producer or converter to the form and physical condition desired for fabrication into parts that will later be given final heat treatment to achieve the desired magnetic characteristics. It covers materials supplied in the form of forging billets, hot-rolled plate, strip, and bar; cold-finished bar; cold-rolled and annealed sheet and strip; shaped wire; and wire.

1.2.1 This specification doesn't not cover either powder metallurgically produced or cast parts.

1.2.2 This specification lists requirements for strip products having isotropic or semi-isotropic magnetic properties but does not include requirements for anisotropic or square hysteresis loop alloys or alloys processed to yield flattened hysteresis loops by use of heat treatments in an applied magnetic field.

1.2.3 This specification does not cover alloys modified by the addition of elements such as sulfur and selenium to enhance machinability.

1.3 The values stated in either customary (cgs-emu and inch-pound) units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with this specification.

 
2. Referenced Documents

A480/A480M-25b

Standard Specification for General Requirements for Flat-Rolled Stainless and Heat-Resisting Steel Plate, Sheet, and Strip (Includes all amendments and changes 9/10/2025).

A484/A484M-24b

Standard Specification for General Requirements for Stainless Steel Bars, Billets, Shapes, and Forgings (Includes all amendments and changes 9/5/2024).

A555/A555M-23

Standard Specification for General Requirements for Stainless Steel Wire and Wire Rods

A596/A596M-21

Standard Test Method for Direct-Current Magnetic Properties of Materials Using the Point by Point (Ballistic) Method and Ring Specimens

A772/A772M-00(2022)

Standard Test Method for AC Magnetic Permeability of Materials Using Sinusoidal Current

A340-23a

Standard Terminology of Symbols and Definitions Relating to Magnetic Testing (Includes all amendments and changes 12/19/2023).

E527-23

Standard Practice for Numbering Metals and Alloys in the Unified Numbering System (UNS)

E1019-24

Standard Test Methods for Determination of Carbon, Sulfur, Nitrogen, and Oxygen in Steel, Iron, Nickel, and Cobalt Alloys by Combustion and Inert Gas Fusion Techniques

A341/A341M-16(2022)

Standard Test Method for Direct Current Magnetic Properties of Soft Magnetic Materials Using D-C Permeameters and the Point by Point (Ballistic) Test Methods

A34/A34M-06(2021)

Standard Practice for Sampling and Procurement Testing of Magnetic Materials

A773/A773M-21

Standard Test Method for Direct Current Magnetic Properties of Low Coercivity Magnetic Materials Using Hysteresigraphs