This specification covers technically important, commercially available, magnetically hard sintered ceramic ferrite permanent magnets. Both barium and strontium ferrite materials are covered by this specification. Both isotropic (1 type) and anisotropic (12 types) are covered. A cross reference to both IEC and MMPA designations is provided. The magnetic property requirements for each type are defined as is the method of test. Other defined requirements include the workmanship. Typical physical properties are listed in the appendices.
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1.1 This specification covers technically important, commercially available, magnetically hard sintered ceramic ferrite permanent magnets.
1.2 Ceramic ferrite magnets have residual magnetic induction Br from 2000 G (0.2 T) up to about 5000 G (0.5 T) and intrinsic coercive field strength Hci (HcJ) from 2000 Oe (160 kA/m) up to about 5000 Oe (400 kA/m). Their specific magnetic hysteresis behavior (demagnetization curve) can be characterized using Test Method A 977/A 977M.
1.3 The values stated in customary (cgs-emu and inch-pound) units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units which are provided for information only and are not considered standard.
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.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
A340 Terminology of Symbols and Definitions Relating to Magnetic Testing
A977/A977M Test Method for Magnetic Properties of High-Coercivity Permanent Magnet Materials Using Hysteresigraphs
InternationalAirTran Dangerous Goods Regulations, Packing Instruction 902 Available from IATA, 800 Place Victoria, PO Box 113, Montral, Quebec, H4Z 1M1.
ceramic ferrite; ceramic magnet; coercive field strength; ferrite magnet; hard ferrite; magnetic induction; magnetic properties; permanent magnet; sintered ceramic ferrite; sintered ferrite magnet;
ICS Number Code 29.030 (Magnetic materials)
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Citing ASTM Standards
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