1.1 该试验方法用于确定结节率和单位面积结节数（即每毫米结节数 2. )使用球墨铸铁中石墨的光学显微镜图像。其他设备（如扫描电子显微镜）生成的图像没有专门处理，但如果系统在两个方面都进行了校准，则可以使用 x 和 y 方向。 1.2 其他类型的铸铁，例如可锻铸铁或石墨工具钢中的二次碳或回火碳的测量，由于此类等级固有的石墨形状和尺寸不同，因此未具体包含在本标准中 1.3 本标准仅涉及推荐的测试方法，其中的任何内容都不应被解释为定义或确定测试材料的可接受性或适用性限制。 1.4 以国际单位制表示的数值应视为标准。本标准不包括其他计量单位。 1.5 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的使用者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。 1.6 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《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====== 5.1 使用视觉估计对“结节性”和“结节数”进行定性测量已经实践了多年。这些方法的再现性和重复性较差。 计算机辅助图像分析的引入使金相学家能够高精度地测量和计数微观结构中感兴趣的单个颗粒。与视觉估计方法相比，这大大减少了测量变化（例如，参见测试方法 第247页 ). 5.2 该方法定义了测量铸铁微观结构中球晶石墨的结节数量和球化质量的程序。铸件或铸造试样中的试样位置以及平面方向- 抛光，由产品标准管理。当没有定义产品标准时，根据需要随机选择测试位置或在特定的系统选择的深度。抛光平面可以与固化方向平行或垂直，也可以根据研究需要随机选择。 5.3 该试验方法可用于确定给定试样内、铸件中给定位置内、铸件不同位置之间或不同铸件中相同位置随时间的变化。 该测试方法的结果可用于根据买方和制造商之间商定的指南对材料进行装运鉴定，也可用于监测工艺质量或产品变化。 5.4 使用计算机控制的自动图像分析系统进行测量。 5.5 待评估样品的最小数量和最小表面积可由生产商-采购商协议确定，前提是测量到至少500个符合最小尺寸要求的颗粒。分析的颗粒数量应在最终分析报告中注明（见 9.6 ).

1.1 This test method is used to determine the percent nodularity and the nodule count per unit area (that is, number of nodules per mm 2 ) using a light microscopical image of graphite in nodular cast iron. Images generated by other devices, such as a scanning electron microscope, are not specifically addressed, but can be utilized if the system is calibrated in both x and y directions. 1.2 Measurement of secondary or temper carbon in other types of cast iron, for example, malleable cast iron or in graphitic tool steels, is not specifically included in this standard because of the different graphite shapes and sizes inherent to such grades 1.3 This standard deals only with the recommended test method and nothing in it should be construed as defining or establishing limits of acceptability or fitness for purpose of the material tested. 1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.5 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. 1.6 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 ====== 5.1 Qualitative measurement of “nodularity” and “nodule count” using visual estimations has been practiced for many years. These methods suffer from poor reproducibility and repeatability. The introduction of computer-aided image analysis enables metallographers to measure and count individual particles of interest in a microstructure with a high degree of precision. This greatly reduces measurement variations compared to visual estimation methods (see, for example, Test Method A247 ). 5.2 This method defines a procedure for measuring the number of nodules and the quality of nodularity of spherulitic graphite in a cast iron microstructure. The specimen’s location in a casting or cast test specimen, and the orientation of the plane-of-polish, are governed by product standards. When a product standard is not defined, choose the test location randomly or at specific systematically chosen depths as needed. The plane-of-polish may be parallel or perpendicular to the solidification direction, or chosen at random, depending upon the needs of the study. 5.3 This test method may be used to determine variations within a given test specimen, within a given location in a casting, between different locations in a casting, or for the same location in different castings over time. Results from this test method may be used to qualify material for shipment in accordance with guidelines agreed upon between purchaser and manufacturer or can be used to monitor process quality or product variations. 5.4 Measurements are performed using a computer-controlled automatic image analysis system. 5.5 A minimum number of specimens and a minimum surface area to be evaluated may be defined by producer-purchaser agreement, provided at least 500 particles meeting the minimum size requirements are measured. The number of particles analyzed shall be indicated in the final analysis report (see 9.6 ).