1.1 这些实践涵盖了用于收集尽可能代表整个起始材料的少量金属粉末的取样方法，并详细介绍了建议将该数量减少为较小的测试部分的程序，在这些测试部分上可以确定化学、物理和机械性能数据。 1.2 根据其对取样粉末储存和运输条件的适用性，描述了几种取样方法: 1.2.1 实践1A（在第节中描述 6. )— 适用于移动粉末的取样，如从一个容器转移到另一个容器或工艺流时；或从输送机上坠落时；或者在移动的流程中。 这是获得组合形成总样本的几个增量的首选做法。 1.2.2 实践1B（在第节中描述 7. )— 适用于已包装运输的粉末取样，如袋装或桶装。建议使用空心管槽取样器对这些包装粉末进行采样，以获得增量( 7.1.1 ). 或者，当其他方法不可能或不可用时，此处指定的程序( 7.1.2 )可用于使用指定材料和配置的勺子从粉末中随机舀取样品。 1.2.3 实践2（在第节中描述 8. )— 适用于从复合样品中获得试验部分。 对于较大数量的粉末，通常使用溜槽分离器，而对于较小数量的粉末，则使用旋转复飞器。 1.3 这些实践适用于粒径通常小于1毫米的颗粒材料或颗粒混合物，包括含有润滑剂的混合物，含或不含其他非金属添加剂，可随时压实。 1.4 这些规程不包括片状粉末或糊状物的取样。有关片状金属粉末和锡膏的取样和测试程序，请参阅测试方法 D480 . 1.5 单位- 以英寸-磅为单位的数值应视为标准值。括号中给出的值是到国际单位制的数学转换，仅供参考，不被视为标准值。 1.6 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。 1.7 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 金属粉末和金属粉末产品的规范和测试方法要求从大量粉末中抽取小样本进行采样、测试和性能评估。 抽样程序与测试和评估同等重要；所用的取样方法必须包括一切预防措施，以确保获得的样品将显示其所代表的大量粉末的真实性质和状况。 4.2 任何取样程序的主要目标都是获得少量真正代表所取大量材料的材料，这种情况易于理解，但难以定义、量化和证明。需要满足以下条件: 3. 4.2.1 每个采样增量应有一个 非零概率 被选中。 4.2.2 所有增量都应该有一个 等概率 被选中。 4.2.3 取样程序 不应改变 材料（例如，通过改变粒度或化学成分）。 4.3 采样a 移动 粉末有助于满足这些标准；因此，应尽可能使用规程1A来获得复合样品。同样，应使用实践2获得试验部分；在可能和可行的情况下，最好使用旋转复飞器。 4.4 虽然并不总是符合 4.2.1 – 4.2.3 ，本标准中描述的其他采样实践基于粉末冶金行业在颗粒金属粉末采样方面久经考验的经验。这些实践表明，所产生的样本提供了可靠和具有代表性的评估数据。 4.5 由于许多测试都是使用极少量的粉末来进行的，因此以标准化的方式获得测试部分是最重要的。本文所述的实践考虑了在填充容器期间和之后金属粉末分离的可能性。 4.6 金属粉末的样本量用于化学分析和确定粉末的物理特性。这些数据用于成品批次的生产控制和质量检查。 4.7 由粉末样品生产的压坯用于评估金属粉末的压实性能，这些信息对于在粉末冶金轴承和结构零件制造中使用这些粉末非常重要。 4.8 将金属粉末样品制成的试样压实并烧结，用于测量固体粉末冶金材料的物理和机械性能。获得的数据包含在粉末冶金材料规范中，以协助粉末冶金应用的材料选择。 4.9 固体粉末冶金制品结构零件、轴承等——由金属粉末样品制成，用于评估此类制品制造和最终使用中的粉末性能。

1.1 These practices cover sampling methods used to collect a small quantity of metal powder that is as representative of the entire starting material as possible, and detail the procedures that are recommended for reducing this quantity into smaller test portions on which chemical, physical, and mechanical property data may be determined. 1.2 Several sampling practices are described, depending on their applicability to the conditions of storage and transport of the sampled powders: 1.2.1 Practice 1A (Described in Section 6 )— Applicable to sampling moving powders, as when being transferred from one container to another or to a process stream; or when falling from a conveyor; or in a moving process stream. This is the preferred practice for obtaining the several increments that are combined to form the gross sample. 1.2.2 Practice 1B (Described in Section 7 )— Applicable to sampling powders that have already been packaged for transport, as in a bag or drum. A hollow tubular slot sampler is the recommended way to sample these packaged powders to obtain the increments ( 7.1.1 ). Alternatively, when other methods are not possible or available, a procedure specified here ( 7.1.2 ) may be used to randomly scoop samples from the powder, using a scoop of specified material and configuration. 1.2.3 Practice 2 (Described in Section 8 )— Applicable to obtaining test portions from the composite sample. For larger quantities of powder, a chute splitter is generally used, while a spinning riffler is used for smaller quantities. 1.3 These practices apply to particulate materials or mixtures of particulates with particle sizes generally less than one millimetre and include mixtures containing lubricant, with or without other non-metallic additives, that are ready for compacting. 1.4 These practices do not cover the sampling of flake powders or pastes. For procedures on the sampling and testing of flake metal powders and pastes, refer to Test Methods D480 . 1.5 Units— The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.6 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. 1.7 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 Specifications and test methods for metal powders and metal powder products require the sampling, testing, and performance evaluation of small samples taken from large quantities of powder. The sampling procedure is equally as important as the testing and evaluation; the sampling methods used must include every precaution to ensure that the samples obtained will show the true nature and condition of the large powder quantity that they represent. 4.2 The primary objective of any sampling procedure is to obtain a small quantity of material that is truly representative of the larger amount from which it is taken, a condition that is readily comprehended but difficult to define, quantify, and prove. Certain criteria are desirable to meet this condition: 3 4.2.1 Every sampling increment should have a non-zero probability of being selected. 4.2.2 All increments should have an equal probability of being selected. 4.2.3 The sampling procedure should not alter the material (for example, by changing the particle size or chemical composition). 4.3 Sampling a moving powder helps to satisfy these criteria; therefore, Practice 1A should be used whenever possible to obtain the composite sample. Similarly, Practice 2 should be used to obtain the test portions; use of a spinning riffler is preferred when possible and practicable. 4.4 Although not always meeting all the criteria of 4.2.1 – 4.2.3 , the other sampling practices described in this standard are based on time-proven experience in the PM industry in sampling granular metal powders. These practices have been shown to produce samples that give reliable and representative evaluation data. 4.5 Since many tests are performed using very small amounts of powder meant to represent much larger quantities, it is most important that the test portions be obtained in a standardized manner. The practices described here take into account the possibility of segregation of the metal powder during and after filling of containers. 4.6 Sample quantities of metal powder are used for chemical analysis and to determine the physical characteristics of the powder. These data are used for production control and quality inspection of finished lots. 4.7 Green compacts produced from powder samples are used to evaluate the compactability properties of metal powders, information that is important to the use of these powders in the manufacture of PM bearings and structural parts. 4.8 Test specimens produced from metal powder samples are compacted and sintered and used to measure physical and mechanical properties of solid PM materials. The data obtained are included in PM material specifications to assist with material selection for PM applications. 4.9 Solid PM articles—structural parts, bearings, etc.—are produced from metal powder samples to evaluate powder performance in the manufacturing and end use of such articles.