Active Standard ASTM C958 | Developed by Subcommittee: C21.04
Book of Standards Volume: 15.02
Historical (view previous versions of standard)
This test method details the standard procedures for the determination of the particle size distribution of alumina or quartz powders using X-ray monitoring of gravity sedimentation. This test procedure shall make use of an X-ray sedimentation apparatus, and ultrasonic probe or bath. An aqueous homogeneous dispersion of the specimen is permitted to settle in a cell. The decrease in particle concentration over a programmed settling distance is monitored by an X-ray beam passing through the sedimenting dispersion to a detector. The specimen concentration at any given sedimentation distance is inversely proportional to the X-ray flux and the equivalent diameter (spherical) is calculated from Stokes' law.
This abstract is a brief summary of the referenced standard. It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use and application. ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date.
1.1 This test method covers the determination of the particle size distribution of alumina or quartz powders in the range from 0.5 to 50 m and having a median particle diameter from 2.5 to 10 m using a sedimentation method. This test method is one of several found valuable for the measurement of particle size. Instruments used for this test method employ a constant intensity X-ray beam that is passed through a sedimenting dispersion of particles.
1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
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.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
C242 Terminology of Ceramic Whitewares and Related Products
E177 Practice for Use of the Terms Precision and Bias in ASTM Test Methods
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
ICS Number Code 81.060.10 (Raw materials)