1.1 这些测试方法包括平均粒度的测量，包括比较程序、平面（或Jeffries）程序和截距程序。这些试验方法也可适用于具有类似于对比图中所示金属结构外观的结构的非金属材料。这些试验方法主要适用于单相晶粒结构，但可用于确定多相或多组分试样中特定类型晶粒结构的平均尺寸。 1.2 这些试验方法用于确定晶粒面积、直径或截距长度呈单峰分布的试样的平均晶粒尺寸。这些分布近似为对数正态分布。这些测试方法不包括表征这些分布性质的方法。试验方法中描述了具有双重粒度分布的试样中的粒度表征 E1181 . 试验方法中描述了细粒基质中单个极粗颗粒的测量 E930 . 1.3 这些试验方法仅涉及平面晶粒尺寸的测定，即由剖切面显示的二维晶粒截面的表征。空间晶粒尺寸的测定，即试样体积中三维晶粒尺寸的测量，超出了这些试验方法的范围。 1.4 这些测试方法描述了使用标准系列分级图表图像进行比较方法或使用简单模板进行手动计数的技术。试验方法中描述了使用半自动数字化平板或自动图像分析仪测量粒度 E1382 . 1.5 这些试验方法仅涉及推荐的试验方法，其中的任何内容都不应解释为定义或确立了受试材料的可接受性或适用性极限。 1.6 测量值以国际单位制表示，视为标准。列出的等效英寸-磅值在括号中，可能是近似值。 1.7 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。 1.8 段落按以下顺序出现: 部分 数字 范围 1. 参考文件 2. 术语 3. 意义和用途 4. 应用概述 5. 采样 6. 试样 7. 标定 8. 显微照片的制备 9 比较程序 10 平面（Jeffries）程序 11 一般拦截程序 12 海恩线性截距程序 13 循环拦截程序 14 Hilliard单圆程序 14.2 艾布拉姆斯三圆程序 14.3 统计分析 15 具有非等轴晶粒形状的试样 16 含有两个或多个相或成分的样本 17 汇报 18 精度和偏差 19 关键词 20 附件: ASTM粒度数字的基础 附件A1 各种粒度测量之间的转换方程 附件A2 奥氏体晶粒度、铁素体钢和奥氏体钢 附件A3 断裂粒度法 附件A4 锻铜和铜基合金的要求 附件A5 特殊情况下的应用 附录A6 附录: 实验室间粒度测定结果 附录X1 参考附件 附录X2 1.9 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====== 4.1 这些试验方法涵盖了全部或主要由单相组成的所有金属的平均晶粒度的估算程序和表示规则。具有两相或一个相和一个组分的试样的粒度可以使用两种方法的组合进行测量，即测量相的体积分数和截距或平面计数（见第节） 17 ). 试验方法也可用于任何外观类似于对比图中所示金属结构的结构。粒度估算的三个基本程序是: 4.1.1 比较程序- 比较过程不需要计算颗粒、截距或交点，但顾名思义，涉及将颗粒结构与一系列分级图像进行比较，这些图像可以是挂图、透明塑料覆盖层或目镜十字线。 在比较晶粒度评级中似乎存在普遍偏见，即晶粒度稍粗( 1. / 2. 至1 G 数字低于实际值（参见 X1.3.5 ). 比较图额定值的重复性和再现性通常为±1粒径数。 4.1.2 平面测量程序- 平面法涉及已知区域内晶粒数量的实际计数。单位面积的颗粒数， N A. ，用于确定ASTM粒度数， G . 该方法的精度是计数颗粒数的函数。只要付出合理的努力，即可达到±0.25粒度单位的精度。结果无偏差，重复性和再现性小于±0.5粒度单位。准确的计数确实需要在计数时标出颗粒。 4.1.3 拦截程序- 截距法涉及每单位测试线长度上测试线截获的晶粒数或与测试线的晶界交点数的实际计数，用于计算平均线性截距长度， ℓ . ℓ 用于确定ASTM粒度数， G . 该方法的精度是计数的拦截或交点数量的函数。只要付出合理的努力，即可获得优于±0.25粒度单位的精度。结果无偏差；重复性和再现性小于±0.5粒度单位。由于无需标出截距或交点即可进行准确计数，因此在相同精度水平下，截距法比平面法更快。 4.2 对于由等轴晶粒组成的试样，将试样与标准图表进行比较的方法最为方便，并且对于大多数商业用途而言足够精确。 为了在确定平均粒度时获得更高的精度，可以使用截距或平面测量程序。截距程序对于由细长晶粒组成的结构特别有用（见第节） 16 ). 4.3 如有争议，平面测量程序应为所有情况下的裁判程序。 4.4 不得试图估算严重冷加工材料的平均晶粒度。如果需要测量晶粒尺寸，则可以认为部分再结晶变形合金和轻度至中度冷加工材料由非等轴晶粒组成。 4.5 单个谷物测量不应基于标准比较图。 这些图表反映了当平面通过三维晶粒阵列时，晶粒尺寸的典型对数正态分布。 由于它们显示了晶粒尺寸的分布，从非常小到非常大，取决于平面截面和晶粒三维阵列的关系，因此图表不适用于单个晶粒的测量。

1.1 These test methods cover the measurement of average grain size and include the comparison procedure, the planimetric (or Jeffries) procedure, and the intercept procedures. These test methods may also be applied to nonmetallic materials with structures having appearances similar to those of the metallic structures shown in the comparison charts. These test methods apply chiefly to single phase grain structures but they can be applied to determine the average size of a particular type of grain structure in a multiphase or multiconstituent specimen. 1.2 These test methods are used to determine the average grain size of specimens with a unimodal distribution of grain areas, diameters, or intercept lengths. These distributions are approximately log normal. These test methods do not cover methods to characterize the nature of these distributions. Characterization of grain size in specimens with duplex grain size distributions is described in Test Methods E1181 . Measurement of individual, very coarse grains in a fine grained matrix is described in Test Methods E930 . 1.3 These test methods deal only with determination of planar grain size, that is, characterization of the two-dimensional grain sections revealed by the sectioning plane. Determination of spatial grain size, that is, measurement of the size of the three-dimensional grains in the specimen volume, is beyond the scope of these test methods. 1.4 These test methods describe techniques performed manually using either a standard series of graded chart images for the comparison method or simple templates for the manual counting methods. Utilization of semi-automatic digitizing tablets or automatic image analyzers to measure grain size is described in Test Methods E1382 . 1.5 These test methods deal only with the recommended test methods and nothing in them should be construed as defining or establishing limits of acceptability or fitness of purpose of the materials tested. 1.6 The measured values are stated in SI units, which are regarded as standard. Equivalent inch-pound values, when listed, are in parentheses and may be approximate. 1.7 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. 1.8 The paragraphs appear in the following order: Section Number Scope 1 Referenced Documents 2 Terminology 3 Significance and Use 4 Generalities of Application 5 Sampling 6 Test Specimens 7 Calibration 8 Preparation of Photomicrographs 9 Comparison Procedure 10 Planimetric (Jeffries) Procedure 11 General Intercept Procedures 12 Heyn Linear Intercept Procedure 13 Circular Intercept Procedures 14 Hilliard Single-Circle Procedure 14.2 Abrams Three-Circle Procedure 14.3 Statistical Analysis 15 Specimens with Non-equiaxed Grain Shapes 16 Specimens Containing Two or More Phases or Constituents 17 Report 18 Precision and Bias 19 Keywords 20 Annexes: Basis of ASTM Grain Size Numbers Annex A1 Equations for Conversions Among Various Grain Size Measurements Annex A2 Austenite Grain Size, Ferritic and Austenitic Steels Annex A3 Fracture Grain Size Method Annex A4 Requirements for Wrought Copper and Copper-Base Alloys Annex A5 Application to Special Situations Annex A6 Appendixes: Results of Interlaboratory Grain Size Determinations Appendix X1 Referenced Adjuncts Appendix X2 1.9 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 cover procedures for estimating and rules for expressing the average grain size of all metals consisting entirely, or principally, of a single phase. The grain size of specimens with two phases, or a phase and a constituent, can be measured using a combination of two methods, a measurement of the volume fraction of the phase and an intercept or planimetric count (see Section 17 ). The test methods may also be used for any structures having appearances similar to those of the metallic structures shown in the comparison charts. The three basic procedures for grain size estimation are: 4.1.1 Comparison Procedure— The comparison procedure does not require counting of either grains, intercepts, or intersections but, as the name suggests, involves comparison of the grain structure to a series of graded images, either in the form of a wall chart, clear plastic overlays, or an eyepiece reticle. There appears to be a general bias in that comparison grain size ratings claim that the grain size is somewhat coarser ( 1 / 2 to 1 G number lower) than it actually is (see X1.3.5 ). Repeatability and reproducibility of comparison chart ratings are generally ±1 grain size number. 4.1.2 Planimetric Procedure— The planimetric method involves an actual count of the number of grains within a known area. The number of grains per unit area, N A , is used to determine the ASTM grain size number, G . The precision of the method is a function of the number of grains counted. A precision of ±0.25 grain size units can be attained with a reasonable amount of effort. Results are free of bias and repeatability and reproducibility are less than ±0.5 grain size units. An accurate count does require marking off of the grains as they are counted. 4.1.3 Intercept Procedure— The intercept method involves an actual count of the number of grains intercepted by a test line or the number of grain boundary intersections with a test line, per unit length of test line, used to calculate the mean lineal intercept length, ℓ . ℓ is used to determine the ASTM grain size number, G . The precision of the method is a function of the number of intercepts or intersections counted. A precision of better than ±0.25 grain size units can be attained with a reasonable amount of effort. Results are free of bias; repeatability and reproducibility are less than ±0.5 grain size units. Because an accurate count can be made without need of marking off intercepts or intersections, the intercept method is faster than the planimetric method for the same level of precision. 4.2 For specimens consisting of equiaxed grains, the method of comparing the specimen with a standard chart is most convenient and is sufficiently accurate for most commercial purposes. For higher degrees of accuracy in determining average grain size, the intercept or planimetric procedures may be used. The intercept procedure is particularly useful for structures consisting of elongated grains (see Section 16 ). 4.3 In case of dispute, the planimetric procedure shall be the referee procedure in all cases. 4.4 No attempt should be made to estimate the average grain size of heavily cold-worked material. Partially recrystallized wrought alloys and lightly to moderately cold-worked material may be considered as consisting of non-equiaxed grains, if a grain size measurement is necessary. 4.5 Individual grain measurements should not be made based on the standard comparison charts. These charts were constructed to reflect the typical log-normal distribution of grain sizes that result when a plane is passed through a three-dimensional array of grains. Because they show a distribution of grain dimensions, ranging from very small to very large, depending on the relationship of the planar section and the three-dimensional array of grains, the charts are not applicable to measurement of individual grains.