3.1 Sieve analyses are carried out to determine the particle size distribution of powders which, in turn, are used to qualify those materials as to their usefulness in the process under consideration. Since particle size analyses have only relative significance, the results should be considered only where they correlate with process characteristics. The parameter that is being measured in this test is the amount of material that will pass through a cloth having theoretically square openings. It must be remembered that all the holes are not square, nor uniform in size, and the question of whether a given particle will go through is a statistical one. Since each particle size analysis method measures a unique physical parameter, the results from one method may not agree with those from another. Particle size distributions play a role in such properties as bulk density, dustiness, and handling characteristics. Care should be taken, however, when interpretations are made from one or two points (sieves) on the distribution curve.1.1 This test method covers the determination of the particle size distribution of nonplastic ceramic powders such as alumina, silica, feldspar, pyrophyllite, nepheline syenite, talc, titanates, and zircon using wire cloth sieves.1.2 Materials containing a large amount of fines, containing agglomerates, or that are nonfree-flowing, are wet-sieved to remove excessive fines or to disperse agglomerates before performing the test. This technique is not applicable to materials that are, to any degree, water soluble.1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units, or are other customary units (in the case of sieve frame diameter and sieve number), that are provided for information only and are not considered 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.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.
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3.1 This test method is useful to both sellers and purchasers of alumina and quartz powders for determining particle size distributions for materials specifications, manufacturing control, and development and research.1.1 This test method, one of several found valuable for the measurement of particle size, covers the determination of the particle size distribution of alumina or quartz powders (0.6 to 56.0 μm) using electrical sensing zone particle size analyzers. These instruments use an electric current path of small dimensions which is modulated by individual particle passage through an aperture, and produces individual pulses of amplitude proportional to the particle volume.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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.
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