1.1 这些测试方法使用透气性来确定金属粉末和相关化合物的包络比表面积及其相关的平均等效球形直径(0.2至75 μ m)。粉末可以在其“供应”（装运、接收或加工）条件下或在其已经通过实验室程序（例如实践中指定的程序）解聚或研磨后进行分析（“实验室研磨”） B859 所获得的值不是绝对值，而是通常在相对基础上用于控制目的。 1.2 单位- 用于确定密度的密度和质量值除外，其中使用克/立方厘米（g/cm 3 )和克(g)单位是长期的行业惯例；压力单位为cm H 2 O-也是长期实践；SI单位的数值应视为标准值。 1.3 本标准并不旨在解决与其使用相关的所有安全性问题（如果有）。本标准的使用者有责任在使用前建立适当的安全、健康和环境实践并确定法规限制的适用性。 1.4 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》中确立的国际公认的标准化原则制定的。 ======意义和用途====== 4.1 这些测试方法提供了确定包络的程序-粉末的比表面积，由此计算“平均”粒径，假设颗粒是单一尺寸、光滑表面、无孔的球形颗粒。因此，通过这些测试方法获得的值将报告为平均粒度或费希尔数。这些测试方法的结果与所用粉末的质量之间的相关程度将随每个特定应用而变化，并且尚未完全确定。 4.2 这些测试方法通常适用于所有金属粉末和相关化合物，包括碳化物、氮化物和氧化物，用于直径在0.2和75 μ m之间(MIC SAS)或在0.5和50 μ m之间(FSSS)的颗粒。它们不应用于由形状远离等轴的颗粒组成的粉末，即薄片或纤维。在这些情况下，允许使用仅由有关各方协议描述的测试方法。这些试验方法不适用于不同粉末的混合物，也不适用于含有粘合剂或润滑剂的粉末。当粉末含有附聚物时，测量的表面积可能受到附聚程度的影响。解聚方法，例如实践中规定的方法 B859 如果有关各方同意，可以使用。 4.3 当通过MIC SAS或FSSS确定粉末的“平均”粒度时，应清楚地记住，该平均粒度是通过使用仅对均匀尺寸和球形形状的粉末成立的关系来确定粉末的比表面积得出的。因此，这些方法的结果仅是平均粒度的估计。

1.1 These test methods use air permeability to determine an envelope-specific surface area and its associated average equivalent spherical diameter (from 0.2 to 75μm) of metal powders and related compounds. The powders may be analyzed in their “as-supplied” (shipped, received, or processed) condition or after they have been de-agglomerated or milled by a laboratory procedure (“lab milled”) such as that specified in Practice B859 . The values obtained are not intended to be absolute but are generally useful on a relative basis for control purposes. 1.2 Units— With the exception of the values for density and the mass used to determine density, for which the use of the gram per cubic centimetre (g/cm 3 ) and gram (g) units is the longstanding industry practice; and the units for pressure, cm H 2 O - also long-standing practice; the values in SI units are to be regarded as standard. 1.3 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. 1.4 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 ====== 4.1 These test methods provide procedures for determining the envelope-specific surface area of powders, from which is calculated an “average” particle diameter, assuming the particles are monosize, smooth surface, nonporous, spherical particles. For this reason, values obtained by these test methods will be reported as an average particle size or Fisher Number. The degree of correlation between the results of these test methods and the quality of powders in use will vary with each particular application and has not been fully determined. 4.2 These test methods are generally applicable to all metal powders and related compounds, including carbides, nitrides, and oxides, for particles having diameters between 0.2 and 75 μm (MIC SAS) or between 0.5 and 50 μm (FSSS). They should not be used for powders composed of particles whose shape is too far from equiaxed - that is, flakes or fibers. In these cases, it is permissible to use the test methods described only by agreement between the parties concerned. These test methods shall not be used for mixtures of different powders, nor for powders containing binders or lubricants. When the powder contains agglomerates, the measured surface area may be affected by the degree of agglomeration. Methods of de-agglomeration such as that specified in Practice B859 may be used if agreed upon between the parties concerned. 4.3 When an “average” particle size of powders is determined either the MIC SAS or the FSSS, it should be clearly kept in mind that this average size is derived from the determination of the specific surface area of the powder using a relationship that is true only for powders of uniform size and spherical shape. Thus, the results of these methods are only estimates of average particle size.