ASTM C1730-17(2022)
(Test Method)Standard Test Method for Particle Size Distribution of Advanced Ceramics by X-Ray Monitoring of Gravity Sedimentation
Standard Test Method for Particle Size Distribution of Advanced Ceramics by X-Ray Monitoring of Gravity Sedimentation
SIGNIFICANCE AND USE
5.1 This test method is useful to both suppliers and users of powders, as outlined in 1.1 and 1.2, in determining particle size distribution for product specifications, manufacturing control, development, and research.
5.2 Users should be aware that sample concentrations used in this test method may not be what is considered ideal by some authorities, and that the range of this test method extends into the region where Brownian movement could be a factor in conventional sedimentation. Within the range of this test method, neither the sample concentration nor Brownian movement is believed to be significant. Standard reference materials traceable to national standards, of chemical composition specifically covered by this test method, are available from NIST,3 and perhaps other suppliers.
5.3 Reported particle size measurement is a function of the actual particle dimension and shape factor as well as the particular physical or chemical properties being measured. Caution is required when comparing data from instruments operating on different physical or chemical parameters or with different particle size measurement ranges. Sample acquisition, handling, and preparation can also affect reported particle size results.
5.4 Suppliers and users of data obtained using this test method need to agree upon the suitability of these data to provide specification for and allow performance prediction of the materials analyzed.
SCOPE
1.1 This test method covers the determination of particle size distribution of advanced ceramic powders. Experience has shown that this test method is satisfactory for the analysis of silicon carbide, silicon nitride, and zirconium oxide in the size range of 0.1 up to 50 µm.
1.1.1 However, the relationship between size and sedimentation velocity used in this test method assumes that particles sediment within the laminar flow regime. It is generally accepted that particles sedimenting with a Reynolds number of 0.3 or less will do so under conditions of laminar flow with negligible error. 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 in water with a Reynolds number greater than 0.3 if large particles 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 following equation:
where:
D = the diameter of the largest particle expected to be present, in cm, ρ = the particle density, in g/cm3, ρ0 = the suspending liquid density, in g/cm3, g = the acceleration due to gravity, 981 cm/sec2, and η = the suspending liquid viscosity, in poise.
1.1.2 A table of the largest particles that can be analyzed with a suggested maximum Reynolds number of 0.3 or less in water at 35 °C is given for a number of materials in Table 1. A column of the Reynolds number calculated for a 50-µm particle sedimenting in the same liquid system is also given for each material. Larger particles can be analyzed in dispersing media with viscosities greater than that for water. Aqueous solutions of glycerine or sucrose have such higher viscosities.
1.2 The procedure described in this test method may be applied successfully to other ceramic powders in this general size range, provided that appropriate dispersion procedures are developed. It is the responsibility of the user to determine the applicability of this test method to other materials. Note however that some ceramics, such as boron carbide and boron nitride, may not absorb X-rays sufficiently to be characterized by this analysis method.
1.3 The values stated in cgs units are to be regarded as the standard, which is the long-standing industry practice. The values given in parentheses are for information onl...
General Information
Relations
Standards Content (Sample)
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.
Designation: C1730 − 17 (Reapproved 2022)
Standard Test Method for
Particle Size Distribution of Advanced Ceramics by X-Ray
Monitoring of Gravity Sedimentation
This standard is issued under the fixed designation C1730; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope with viscosities greater than that for water. Aqueous solutions
of glycerine or sucrose have such higher viscosities.
1.1 This test method covers the determination of particle
size distribution of advanced ceramic powders. Experience has
1.2 The procedure described in this test method may be
shown that this test method is satisfactory for the analysis of
applied successfully to other ceramic powders in this general
silicon carbide, silicon nitride, and zirconium oxide in the size
size range, provided that appropriate dispersion procedures are
range of 0.1 up to 50 µm.
developed. It is the responsibility of the user to determine the
1.1.1 However, the relationship between size and sedimen-
applicability of this test method to other materials. Note
tation velocity used in this test method assumes that particles
however that some ceramics, such as boron carbide and boron
sediment within the laminar flow regime. It is generally
nitride, may not absorb X-rays sufficiently to be characterized
accepted that particles sedimenting with a Reynolds number of
by this analysis method.
0.3 or less will do so under conditions of laminar flow with
1.3 The values stated in cgs units are to be regarded as the
negligible error. Particle size distribution analysis for particles
standard, which is the long-standing industry practice. The
settling with a larger Reynolds number may be incorrect due to
values given in parentheses are for information only.
turbulent flow. Some materials covered by this test method
1.4 This standard does not purport to address all of the
may settle in water with a Reynolds number greater than 0.3 if
safety concerns, if any, associated with its use. It is the
large particles are present. The user of this test method should
responsibility of the user of this standard to establish appro-
calculate the Reynolds number of the largest particle expected
priate safety, health, and environmental practices and deter-
to be present in order to judge the quality of obtained results.
mine the applicability of regulatory limitations prior to use.
Reynolds number (Re) can be calculated using the following
Specific hazard information is given in Section 8.
equation:
1.5 This international standard was developed in accor-
D ρ 2 ρ ρ g
~ !
0 0
Re 5 (1) dance with internationally recognized principles on standard-
18η
ization established in the Decision on Principles for the
where:
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
D = the diameter of the largest particle expected to be
Barriers to Trade (TBT) Committee.
present, in cm,
ρ = the particle density, in g/cm ,
ρ = the suspending liquid density, in g/cm ,
2. Referenced Documents
g = the acceleration due to gravity, 981 cm/sec , and
2.1 ASTM Standards:
η = the suspending liquid viscosity, in poise.
C1145 Terminology of Advanced Ceramics
1.1.2 A table of the largest particles that can be analyzed
E1617 Practice for Reporting Particle Size Characterization
with a suggested maximum Reynolds number of 0.3 or less in
Data
water at 35 °C is given for a number of materials in Table 1.A
columnoftheReynoldsnumbercalculatedfora50-µmparticle
3. Terminology
sedimenting in the same liquid system is also given for each
3.1 For definitions of terms used in this test method, refer to
material. Larger particles can be analyzed in dispersing media
Terminology C1145.
This test method is under the jurisdiction of ASTM Committee C28 on
Advanced Ceramics and is the direct responsibility of Subcommittee C28.03 on
Physical Properties and Non-Destructive Evaluation. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved Feb. 1, 2022. Published February 2022. Originally contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
approved in 2017. Last previous edition approved in 2017 as C1730 – 17. DOI: Standards volume information, refer to the standard’s Document Summary page on
10.1520/C1730-17R22. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1730 − 17 (2022)
TABLE 1 Maximum Diameter of Ceramic Powders That Can Be Analyzed with Reynolds Number of 0.3 or Less in Water at 35 °C
A
Particle Composition Particle Density Maximum Particle Diameter, µm Reynolds Number for 50 µm
Aluminum Nitride 3.26 50.36 0.29
Aluminum Oxide 3.965 46.01 0.39
Cerium Dioxide 7.132 36.13 0.80
Silicon Carbide 3.217 50.68 0.29
Silicon Nitride 3.44 49.09 0.32
Yttrium Oxide 5.01 41.61 0.52
Zirconium Oxide 5.89 38.95 0.63
A 3
A Reynolds number calculated for 50-µm particles sedimenting in water at 35 °C, with a density of 0.9941 g/cm and viscosity of 0.7225 cp. Entries with Reynolds
numbers that exceed the recommended upper limit of 0.30 are included to indicate that samples of these materials containing 50-µm particles should not be analyzed using
water as a dispersing liquid without addition of a viscosity modifier such as glycerol or sucrose.
4. Summary of Test Method X-rays to determine particle mass concentration as a homoge-
neous dispersion of sample sediments under the influence of
4.1 A carefully dispersed, homogeneous suspension of the
gravity.
powder is permitted to settle in a cell scanned by a collimated
X-ray beam of constant intensity. The net X-ray signal is 6.2 Ultrasonic Probe, consisting of a 200 to 300 W power
inversely proportional to the sample concentration in the unit, ultrasonic transducer, and 13-mm ( ⁄2-in.) diameter probe.
dispersing medium, and the particle diameter is related to the
6.3 Balance, top-loading, accurate to 100 6 0.1 g.
position of the X-ray beam relative to the top of the cell.
6.4 Stirrer, magnetic, with 19-mm ( ⁄4-in.) stirrer bar.
Cumulative mass percent versus equivalent spherical diameter
is recorded to yield a particle size distribution curve.
7. Reagents and Materials
7.1 Purity of Reagents—Reagent-grade chemicals shall be
5. Significance and Use
used in all tests. Unless otherwise indicated, it is intended that
5.1 This test method is useful to both suppliers and users of
all reagents conform to the specifications of the Committee on
powders,asoutlinedin1.1and1.2,indeterminingparticlesize
Analytical Reagents of the American Chemical Society where
distribution for product specifications, manufacturing control,
such specifications are available. Other grades may be used,
development, and research.
provided it is first ascertained that the reagent is of sufficiently
5.2 Users should be aware that sample concentrations used
high purity to permit its use without lessening the accuracy of
inthistestmethodmaynotbewhatisconsideredidealbysome
the determination.
authorities, and that the range of this test method extends into
7.2 Typical Dispersing Media—Dissolve 5.0 g of sodium
the region where Brownian movement could be a factor in
hexametaphosphate [(NaPO ) ] in 1000 mL of distilled or
3 6
conventional sedimentation. Within the range of this test
deionized water.Alternately, dissolve 5.0 g Darvan C (ammo-
method, neither the sample concentration nor Brownian move-
nium salt of polymethacrylic acid) in 95 mL of distilled or
ment is believed to be significant. Standard reference materials
deionized water. This latter solution is typically used after
traceable to national standards, of chemical composition spe-
dilution of 0.03 g per 20 mL of distilled or deionized water.
cifically covered by this test method, are available from NIST,
7.3 pH Adjusters—Freshammoniumhydroxide(NH OH)at
and perhaps other suppliers.
5 to 10 weight % strength is a common reagent used to raise
5.3 Reported particle size measurement is a function of the
pH,whilefreshnitricacid(HNO )at5to10weight%strength
actual particle dimension and shape factor as well as the
is a common reagent to lower pH.
particular physical or chemical properties being measured.
Caution is required when comparing data from instruments 7.4 Cleaning Solution—Prepare a 0.1 % solution by volume
of Triton X-100 using distilled or deionized water, or other
operating on different physical or chemical parameters or with
differentparticlesizemeasurementranges.Sampleacquisition, suitable laboratory cleaning solution.
handling, and preparation can also affect reported particle size
results.
The sole instrument of this type known to the committee at this time is the
SediGraph X-ray gravity sedimentation particle size analyzer, available from
5.4 Suppliers and users of data obtained using this test
Micromeritics Instrument Corporation, 4356 Communications Drive, Norcross, GA
method need to agree upon the suitability of these data to
30093. If you are aware of alternative suppliers, please provide this information to
provide specification for and allow performance prediction of
ASTM International Headquarters. Your comments will receive careful consider-
ation at a meeting of the responsible technical committee, which you may attend.
the materials analyzed.
Reagent Chemicals, American Chemical Society Specifications, American
Chemical Society, Washington, DC. For suggestions on the testing of reagents not
6. Apparatus
listed by the American Chemical Society, see Analar Standards for Laboratory
Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia
6.1 X-Ray Gravitational Sedimentation Particle Size
and National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,
Analyzer—The analyzer shall utilize extinction of collimated
MD.
Darvan C is a trademarked product of R.T.Vanderbilt Company, Inc., Norwalk,
CT 06856-5150.
3 7
National Institute of Standards and Technology (NIST), 100 Bureau Dr., Stop Triton X-100 is a trademarked product of Rohm & Haas, Philadelphia, PAand
2300, Gaithersburg, MD 20899-2300, http://www.nist.gov. is available from a number of laboratory supply companies.
C1730 − 17 (2022)
8. Hazards 9.2.
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