Metal Powder

Metal powder particle testing standards are published by ASTM and ISO. The documents from ASTM include standard test methods, terminology, practices, and guides for sieve analysis, powder metallurgy, sampling, de-agglomeration, liquid dispersion, x-ray monitoring of gravity sedimentation, and light scattering. ISO 4497 covers determination of particle size by dry sieving.

ASTM B214-16

Standard Test Method for Sieve Analysis of Metal Powders

1.1 This test method covers the dry sieve analysis of metal powders, using sieves with openings ranging from 45 to 850 micrometres. 1.2 This test method is based on a particular type of mechanical sieve shaker (see 5.2 ). Other types of sieve shakers are also available, but their precision and reproducibility have not been determined. 1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 1.4 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 and health practices and determine the applicability of regulatory limitations prior to use.

ASTM B243-20

Standard Terminology of Powder Metallurgy

1.1 This terminology standard includes definitions that are helpful in the interpretation and application of powder metallurgy terms. 1.2 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.

ASTM B215-20

Standard Practices for Sampling Metal Powders

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.

ASTM B859-21

Standard Practice for De-Agglomeration of Refractory Metal Powders and Their Compounds Prior to Particle Size Analysis

1.1 This practice covers the de-agglomeration of refractory metal powders and their compounds in preparation for particle size analysis. 1.2 Experience has shown that this practice is satisfactory for the de-agglomeration of elemental tungsten, molybdenum, rhenium, and tantalum metal powders, and tungsten carbide. Other metal powders (for example, elemental metals, carbides, and nitrides) may be prepared for particle size analysis using this practice with caution as to effectiveness until actual satisfactory experience is developed. 1.3 Units— With the exception of the values for mass, for which the use of the gram (g) unit is the long-standing industry practice, the values stated in SI units are to be regarded as standard. No other units of measure are included in this standard. 1.4 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. For specific precautionary statements, see Note 2 . 1.5 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.

ASTM B821-10(2016)

Standard Guide for Liquid Dispersion of Metal Powders and Related Compounds for Particle Size Analysis

1.1 This guide covers the dispersion in liquids of metal powders and related compounds for subsequent use in particle size analysis instruments. This guide describes a general procedure for achieving and determining dispersion; it also lists procedures that are currently in general use for certain materials. 1.2 This guide is limited to metal powders and related metal compounds. However, the general procedure described herein may be used, with caution as to its significance, for other particulate materials, such as ceramics, pigments, minerals, etc. 1.3 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only. 1.4 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 and health practices and determine the applicability of regulatory limitations prior to use.

ASTM B761-17(2021)

Standard Test Method for Particle Size Distribution of Metal Powders and Related Compounds by X-Ray Monitoring of Gravity Sedimentation

1.1 This test method covers the determination of particle size distributions of metal powders. Experience has shown that this test method is satisfactory for the analysis of elemental tungsten, tungsten carbide, molybdenum, and tantalum powders, all with an as-supplied estimated average particle size of 6 μm or less, as determined by Test Method B330 . Other metal powders (for example, elemental metals, carbides, and nitrides) may be analyzed using this test method with caution as to significance until actual satisfactory experience is developed (see 7.2 ). The procedure covers the determination of particle size distribution of the powder in the following two conditions: 1.1.1 As the powder is supplied (as-supplied), and 1.1.2 After the powder has been deagglomerated by rod milling as described in Practice B859 . 1.2 This test method is applicable to particles of uniform density and composition having a particle size distribution range of 0.1 up to 100 μm. 1.2.1 However, the relationship between size and sedimentation velocity used in this test method assumes that particles sediment within the laminar flow regime. This requires that the particles sediment with a Reynolds number of 0.3 or less. Particle size distribution analysis for particles settling with a larger Reynolds number may be incorrect due to turbulent flow. Some materials covered by this test method may settle with Reynolds number greater than 0.3 if particles greater than 25 μm are present. The user of this test method should calculate the Reynolds number of the largest particle expected to be present in order to judge the quality of obtained results. Reynolds number (Re) can be calculated using the flowing equation A table of the largest particles that can be analyzed with Reynolds number of 0.3 or less in water at 35°C is given for a number of metals in Table 1 . A column of the Reynolds number calculated for a 30"“μm particle sedimenting in the same liquid system is given for each material also. 1.3 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, the values in SI units are to be regarded as standard. 1.4 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. Specific hazard information is given in Section 7 . 1.5 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.

ASTM B822-20

Standard Test Method for Particle Size Distribution of Metal Powders and Related Compounds by Light Scattering

1.1 This test method covers the determination of the particle size distribution by light scattering, reported as volume percent, of particulate materials including metals and compounds. 1.2 This test method applies to analyses with both aqueous and nonaqueous dispersions. In addition, analysis can be performed with a gaseous dispersion for materials that are hygroscopic or react with a liquid carrier. 1.3 This test method is applicable to the measurement of particulate materials in the range of 0.4 to 2000 m, or a subset of that range, as applicable to the particle size distribution being measured. 1.4 Units 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.

ISO 4497:2020

Metallic powders - Determination of particle size by dry sieving

This document specifies a method of determining the particle size distribution of metallic powders by dry sieving into size fractions. The method is applicable to dry, unlubricated metallic powders, but not applicable to powders in which the morphology differs markedly from being equiaxial, for example flake-type powders. The method is not applicable to metallic powders having a particle size wholly or mostly under 45 µm.