1.1 本试验方法包括直流测试，用于测定环形、环形、链状、双叠爱泼斯坦磁芯或其他标准形状材料的基本磁性，这些材料可以从铸造、压实、烧结、锻造或轧制材料上切割、冲压、机加工或研磨。它包括在直流磁场强度陡波前反转的条件下确定正常磁化曲线和磁滞回线的测试。 1.2 本试验方法应结合实践使用 A34/A34M . 1.3 该测试方法适用于从极低磁场强度到200 Oe或更高[15.9 kA/m或更高]的测试范围。下限由积分器灵敏度确定，上限由磁化绕组中的发热确定。特殊技术和短时测试可能会延长磁场强度的上限。 1.4 本测试方法下的测试本质上比其他方法更准确。当观察到规定的尺寸或形状要求时，测量值非常接近绝对特性。可用的测试精度主要受到仪器精度的限制。在大多数情况下，可以使用试验方法获得等效结果 A773/A773M 或IEC出版物60404-4的试验方法。 1.5 本试验方法允许选择试样，以允许在不受外部轭系统干扰的情况下，在相对于晶体取向的任何期望方向上测量性能。 1.6 本试验方法中使用的符号和缩写定义见 图1 和部分 5. , 6. , 9 和 10 . 官方定义见术语 A340型 . 图1 使用环形磁芯的基本电路 注1: A. 1. -多量程电流表，主磁化电流电路 A. 2. -多量程电流表，滞后电流电路 N 1. -磁化（初级）绕组 N 2. -磁通感应（二次）绕组 F -电子积分器 R 1. -主电流控制变阻器 R 2. -滞环电流控制变阻器 S 1. -换向开关 S 2. -磁滞电流控制变阻器的分流开关 1.7 警告- 环保局和许多国家机构已将汞指定为一种有害物质，可导致中枢神经系统、肾脏和肝脏损害。汞或其蒸汽可能对健康有害，并对材料具有腐蚀性。处理汞和含汞产品时应小心。有关详细信息，请参阅适用的产品材料安全数据表（MSDS）和EPA网站( http://www.epa.gov/mercury/faq.htm )了解更多信息。用户应意识到，州法律可能禁止在您所在州销售汞或含汞产品，或同时销售两者。 1.8 以常规（cgs-emu和英寸-磅）单位或国际单位表示的值应单独视为标准值。在本试验方法中，除与计算有关的章节外，括号中显示了国际单位制，其中各单位制有单独的章节。每个系统中规定的值不是精确的等价物；因此，每个系统应相互独立使用。结合两个系统的值可能会导致与该方法不一致。 1.9 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.10 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 3.1 使用合适环形试样的试验方法 4. 是确定由于没有退磁效应而导致的材料基本磁性的首选方法，非常适合规范验收、服务评估和研发。 3.2 如果试样代表大块材料，通常是薄带材和线材的情况，则该试验也适用于设计目的。 3.3 当试样不一定代表大块材料（如大型锻件或铸件加工的环）时，本试验方法的结果可能无法准确指示大块材料的磁性。在这种情况下，在过去性能历史背景下查看的测试结果将有助于判断当前材料是否适合预期应用。

1.1 This test method covers dc testing for the determination of basic magnetic properties of materials in the form of ring, toroidal, link, double-lapped Epstein cores, or other standard shapes which may be cut, stamped, machined, or ground from cast, compacted, sintered, forged, or rolled materials. It includes tests for determination of the normal magnetization curve and hysteresis loop taken under conditions of steep wavefront reversals of the direct-current magnetic field strength. 1.2 This test method shall be used in conjunction with Practice A34/A34M . 1.3 This test method is suitable for a testing range from very low magnetic field strength up to 200 or more Oe [15.9 or more kA/m]. The lower limit is determined by integrator sensitivity and the upper limit by heat generation in the magnetizing winding. Special techniques and short duration testing may extend the upper limit of magnetic field strength. 1.4 Testing under this test method is inherently more accurate than other methods. When specified dimensional or shape requirements are observed, the measurements are a good approximation to absolute properties. Test accuracy available is primarily limited by the accuracy of instrumentation. In most cases, equivalent results may be obtained using Test Method A773/A773M or the test methods of IEC Publication 60404-4. 1.5 This test method permits a choice of test specimen to permit measurement of properties in any desired direction relative to the direction of crystallographic orientation without interference from external yoke systems. 1.6 The symbols and abbreviated definitions used in this test method appear in Fig. 1 and Sections 5 , 6 , 9 , and 10 . For the official definitions see Terminology A340 . FIG. 1 Basic Circuit Using Ring-Type Cores Note 1: A 1 —Multirange ammeter, main-magnetizing current circuit A 2 —Multirange ammeter, hysteresis-current circuit N 1 —Magnetizing (primary) winding N 2 —Flux-sensing (secondary) winding F —Electronic integrator R 1 —Main current control rheostat R 2 —Hysteresis current control rheostat S 1 —Reversing switch S 2 —Shunting switch for hysteresis current control rheostat 1.7 Warning— Mercury has been designated by EPA and many state agencies as a hazardous material that can cause central nervous system, kidney, and liver damage. Mercury, or its vapor, may be hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury-containing products. See the applicable product Material Safety Data Sheet (MSDS) for details and EPA’s website ( http://www.epa.gov/mercury/faq.htm ) for additional information. Users should be aware that selling mercury or mercury-containing products, or both, in your state may be prohibited by state law. 1.8 The values stated in either customary (cgs-emu and inch-pound) units or SI units are to be regarded separately as standard. Within this test method, the SI units are shown in brackets except for the sections concerning calculations where there are separate sections for the respective unit systems. 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 method. 1.9 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. 1.10 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. ====== Significance And Use ====== 3.1 Test methods using suitable ring-type specimens 4 are the preferred methods of determining the basic magnetic properties of a material caused by the absence of demagnetizing effects and are well suited for specification acceptance, service evaluation, and research and development. 3.2 Provided the test specimen is representative of the bulk material as is usually the case for thin strip and wire, this test is also suitable for design purposes. 3.3 When the test specimen is not necessarily representative of the bulk material such as a ring machined from a large forging or casting, the results of this test method may not be an accurate indicator of the magnetic properties of the bulk material. In such instances, the test results when viewed in context of past performance history will be useful for judging the suitability of the current material for the intended application.