GB/T 14986.1-2025 Soft magnetic alloys—Part 1：General requirements English, Anglais, Englisch, Inglés, えいご
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ICS 77.140.40
CCS H 58
National Standard of the People's Republic of China
GB/T 14986.1-2025
Replaces GB/T 14986.1-2018, GB/T 15013-1994
Soft Magnetic Alloys-Part 1: General Requirements
Issue date: 2025-08-29 Implementation date: 2026-03-01
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
the Standardization Administration of the People's Republic of China
Contents
Foreword
1 Scope
2 Normative References
3 Terms and Definitions
4 Classification and Designation
5 Ordering Information
6 Manufacturing Process
7 Technical Requirements
8 Test Methods
Soft Magnetic Alloys-Part 1: General Requirements
1 Scope
This document provides the classification and designation of soft magnetic alloys, specifies order content, manufacturing processes, technical requirements, inspection rules, packaging, marking, storage, and quality certificates, and describes corresponding test methods.
This document applies to cold-rolled strips, cold-rolled plates, cold-drawn wires, cold-drawn (rolled) tubes, hot-rolled wire rods, hot-rolled plates, hot-rolled ( forged ) bars, and turned or ground bars (hereinafter referred to as "alloy materials").
2 Normative References
The provisions of the following documents constitute essential clauses of this document through normative citations. For dated references, only the edition cited applies; for undated references, the latest version (including all amendments) applies.
GB/T 223 (all parts) Chemical analysis methods for iron and steel
GB/T 3658 Measurement of magnetic properties of soft magnetic metal materials and powder metallurgy materials using ring specimens (20 Hz–100 kHz)
GB/T 8170 Rules for rounding off numerical values and representation and judgment of limiting values
GB/T 13012 Measurement method for DC magnetic properties of soft magnetic materials
GB/T 13297 General rules for packaging, marking, and quality certificates of precision alloys
GB/T 14981 Dimensions, shape, mass, and tolerances for hot-rolled wire rods
GB/T 20066 Sampling and sample preparation for chemical analysis of steel and iron
3 Terms and Definitions
3.1
Soft magnetic alloy: A magnetic alloy that can be easily magnetized under external force and demagnetized after removal of the field, with coercivity generally below 0.8 kA/m.
3.2
Magnetic induction (B): A divergence-free vector quantity that determines the magnitude and direction of a magnetic field at any point in space.
Note: The force F acting on a charge Q moving at velocity v at this point is given by the cross product:
F = Qv × B
3.3
Saturation magnetic induction (Bs): The magnetic induction when a material is magnetized to saturation.
Note: In practice, Bs typically refers to the magnetic induction at a specified field intensity near saturation.
3.4
Remanent magnetic induction (Br): The magnetic induction when the external field strength (including self-demagnetizing field) is zero.
3.5
Remanence (Br): The remanent magnetic induction obtained by monotonically varying the field from saturation.
3.6
Absolute permeability (μ): The ratio of magnetic induction B to field strength H.
3.7
Maximum permeability (μm): The maximum permeability on the initial magnetization curve.
3.8
Inductance permeability (μL): The ratio of magnetic induction to field strength.
Note: A measure of a material's ability to magnetize in a field. For symmetrically cyclically magnetized materials, μL is derived from the inductive component of the circuit representing the sample.
3.9
Elastic permeability (μ'): The real part of complex permeability.
3.10
Coercivity (HcB): The field intensity required to reduce the magnetic induction to zero after saturation.
Note: HcB is typically called magnetic coercivity, while HcJ or HcM is called intrinsic coercivity.
3.11
Specific total loss (Pv): The total power loss per unit mass under specified conditions.
4 Classification and Designation
4.1 Classification
Soft magnetic alloys are classified into four categories based on their primary alloying elements:
Iron-Nickel (Fe-Ni) Alloys
Iron-nickel alloys are further classified into seven subcategories based on their key properties:
Corrosion-resistant iron-nickel alloys
Iron-nickel alloys with higher permeability and higher saturation magnetic induction
High-permeability iron-nickel alloys
Rectangular hysteresis loop iron-nickel alloys
Magnetic temperature compensation iron-nickel alloys
Constant permeability iron-nickel alloys
High-hardness, high-resistance iron-nickel alloys
b) Iron-Cobalt (Fe-Co) Alloys.
c) Iron-Chromium (Fe-Cr) Alloys.
d) Iron-Aluminum (Fe-Al) Alloys. Iron-aluminum alloys are further classified into four subcategories based on their key properties:
Iron-aluminum alloys with higher saturation magnetic induction
Iron-aluminum alloys with higher saturation magnetic induction, higher permeability, and
low remanent magnetic induction
Iron-aluminum alloys with higher magnetostriction coefficient
Iron-aluminum alloys with higher permeability and higher resistivity
4.2 Symbols
The symbols used in GB/T 14986 and their corresponding explanations are provided in Table 1.
Table 1 Symbols and Explanations
5 Ordering Information
