ASTM F660-83(R2019) pdf free download

ASTM F660-83(R2019) pdf free download.Standard Practice for Comparing Particle Size in the Use of Alternative Types of Particle Counters
1. Scope
1.1 This practice provides a procedure for comparing the sizes ofnonspherical particles in a test sample determined with different types ofautomatic particle counters, which operate on different measuring principles. 1.2 A scale factor is obtained by which, in the examination of a given powder, the size scale of one instrument may be multiplied to agree with the size scale of another. 1.3 The practice considers rigid particles, free of fibers, of the kind used in studies of filtration, such as: commercially available test standards of quartz or alumina, or fly ash, or some powdered chemical reagent, such as iron oxide or calcium sulfate. 1.4 Three kinds of automatic particle counters are consid- ered: 1.4.1 Image analyzers, which view stationary particles un- der the microscope and, in this practice, measure the longest end-to-end distance of an individual particle. 1.4.2 Optical counters, which measure the area of a shadow cast by a particle as it passes by a window; and 1.4.3 Electrical resistance counters, which measure the vol- ume of a particle as it passes through an orifice in an electrically conductive liquid. 1.5 This practice also considers the use of instruments that provide sedimentation analyses, which is to say provide measures of the particle mass distribution as a function of Stokes diameter. The practice provides a way to convert mass distribution into number distribution so that the meaning of Stokes diameter can be related to the diameter measured by the instruments in 1.4. 1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 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 appro- priate safety, health, and environmental practices and deter- mine the applicability ofregulatory limitations prior to use.
5. Apparatus
5.1 Automatic Particle Counters: 5.1.1 Any, or all, of the three types are employed: 5.1.1.1 The Image Analyzer—This instrument counts par- ticles by size as those particles lie on a microscope slide. In this practice, size means the longest end-to-end distance. This diameter, in the examples to follow, is designated d e . 5.1.1.2 The Optical Counter—This instrument measures the area of a shadow cast by a particle as it passes a window. From that area the instrument reports the diameter ofa circle ofequal area. This diameter is designated d o . See Practice F661. 5.1.1.3 The Electrical Resistance Counter—This instrument measures the volume of an individual particle. From that volume the instrument reports the diameter ofa sphere ofequal volume. This diameter is designated d v . See Test Method F662. 5.2 Sedimentation Instruments—These instruments provide a measure of the mass distribution of particles (as opposed to the number distributions determined in 5.1). This diameter, the Stokes diameter, is designated d s .
6. Procedure
6.1 Calibrate each particle counter with standard, spherical particles, following the instructions of the manufacturer of the counter. 6.2 Present a known mass ofparticles to the counter. That is, with the image analyzer present a known mass of particles to a field of view; and, with the other counters present a liquid suspension with a known mass concentration of particles. 6.3 In counting particles at the small-diameter end of the spectrum, present at least three different, relatively small, masses of particles. In counting particles at the large-diameter end, present at least three different, relatively large, masses. 6.4 After obtaining the counts (6.3) correct them all to reflect the count of a common mass. For example, correct all counts to show particle distribution for each milligram of solids. Plot the counts in the manner of Fig. 1.