ASTM B821-10(2016)

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

SIGNIFICANCE AND USE
4.1 The method of powder dispersion in a liquid has a significant effect on the results of a particle size distribution analysis. The analysis will show a too-coarse, unstable, or nonrepeatable distribution if the powder has not been dispersed adequately. It is therefore important that parties wishing to compare their analyses use the same dispersion technique.  
4.2 This guide provides established powder dispersion techniques for certain materials and the means of deriving techniques for materials not listed. It should be used by all parties performing liquid-dispersed particle size analysis of all of the materials covered by this guide (see 1.1, 1.2, and 4.1).  
4.3 This guide should be used in the preparation of powders for use in Test Methods B430, B761, and B822 and other procedures that analyze metal powder particle size distributions in liquid-dispersed systems. (A) As described in Test Method B430.(B) Tween 21, chemically known as polyoxyethylene6 sorbitan monolaurate, is manufactured by Croda International PLC, and is available from various chemical suppliers.(C) Three to five drops Tween 21 in 30 to 50 mL water.
SCOPE
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.

General Information

• Status: Historical
• Publication Date: 30-Sep-2016
• ICS: 19.120 - Particle size analysis. Sieving
• Technical Committee: B09 - Metal Powders and Metal Powder Products
• Drafting Committee: B09.02 - Base Metal Powders

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: B821 − 10 (Reapproved 2016)
Standard Guide for
Liquid Dispersion of Metal Powders and Related
Compounds for Particle Size Analysis
This standard is issued under the fixed designation B821; 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 of Gravity Sedimentation
B822 Test Method for Particle Size Distribution of Metal
1.1 This guide covers the dispersion in liquids of metal
Powders and Related Compounds by Light Scattering
powders and related compounds for subsequent use in particle
size analysis instruments. This guide describes a general
3. Terminology
procedure for achieving and determining dispersion; it also
3.1 Definitions—Definitions of powder metallurgy terms
lists procedures that are currently in general use for certain
can be found in Terminology B243.
materials.
4. Significance and Use
1.2 This guide is limited to metal powders and related metal
compounds. However, the general procedure described herein 4.1 The method of powder dispersion in a liquid has a
may be used, with caution as to its significance, for other
significant effect on the results of a particle size distribution
particulatematerials,suchasceramics,pigments,minerals,etc. analysis. The analysis will show a too-coarse, unstable, or
nonrepeatabledistributionifthepowderhasnotbeendispersed
1.3 The values stated in inch-pound units are to be regarded
adequately. It is therefore important that parties wishing to
as the standard. The values given in parentheses are for
compare their analyses use the same dispersion technique.
information only.
4.2 This guide provides established powder dispersion tech-
1.4 This standard does not purport to address all of the
niques for certain materials and the means of deriving tech-
safety concerns, if any, associated with its use. It is the
niques for materials not listed. It should be used by all parties
responsibility of the user of this standard to establish appro-
performing liquid-dispersed particle size analysis of all of the
priate safety and health practices and determine the applica-
materials covered by this guide (see 1.1, 1.2, and 4.1).
bility of regulatory limitations prior to use.
4.3 This guide should be used in the preparation of powders
2. Referenced Documents
for use in Test Methods B430, B761, and B822 and other
2.1 ASTM Standards: procedures that analyze metal powder particle size distribu-
B243 Terminology of Powder Metallurgy tions in liquid-dispersed systems.
B430 Test Method for Particle Size Distribution of Refrac-
5. Apparatus
tory Metal Powders and Related Compounds by Turbidi-
5.1 Microscope, suitable for observation of particles in the
metry
size range of 5 to 1000 µm.
B761 Test Method for Particle Size Distribution of Metal
Powders and Related Compounds by X-Ray Monitoring
5.2 Ultrasonic Probe, ⁄2 -in. (25.4-mm) tip, with the power
level to be determined by this guide.
This guide is under the jurisdiction of ASTM Committee B09 on Metal
5.3 Ultrasonic Bath—Power level to be determined by this
Powders and Metal Powder Products and is the direct responsibility of Subcom-
guide.
mittee B09.02 on Base Metal Powders.
Current edition approved Oct. 1, 2016. Published October 2016. Originally
6. Reagents
approved in 1992. Last previous edition approved 2010 as B821 – 10. DOI:
10.1520/B0821-10R16.
6.1 Purity of Reagents—Reagent grade chemicals should be
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
used in all tests. Unless otherwise indicated, it is intended that
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
all reagents should conform to the specifications of the
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. Committee on Analytical Reagents of the American Chemical
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
B821 − 10 (2016)
TABLE 1 Recommended Dispersion Procedures
Ultrasonic
Treatment
Carrier Surfactant
Material Surfactant
Liquid Concentration
Power
Type Time, min
Level, W
Chromium carbide water none . none . .
A
or
bath
25 5
B C
Copper water Tween 21 3–5 drops bath 80 1
B
Ferroalloys isopropyl alcohol Tween 21 10 % bath 80 1
B C
Iron/steel water Tween 21 3–5 drops bath 80 1
B C
Manganese sulfide water Tween 21 3–5 drops bath 80 1
Molybdenum water sodium hexametaphosphate 0.01 % probe 160 3
or
bath 80 10
A
or
bath
25 5
B C
Nickel water Tween 21 3–5 drops bath 80 1
Tantalum water sodium hexametaphosphate 0.01 % probe 160 3
or
bath 80 10
Tantalum carbide water sodium hexametaphosphate 0.01 % probe 160 3
or
bath 80 10
A
or
bath
25 5
Tungsten water sodium hexametaphosphate 0.01 % probe 160 3
or
bath 80 10
A
or
bath
25 5
Tungsten carbide water sodium hexametaphosphate 0.01 % probe 160 3
or
bath 80 10
A
or
bath
25 5
A
As described in Test Method B430.
B 6
Tween 21, chemically known as polyoxyethylene sorbitan monolaurate, is manufactured by Croda International PLC, and is available from various chemical suppliers.
C
Three to five drops Tween 21 in 30 to 50 mL water.
Society. Other grades may be used, provided it is first
ascertained that the reagent is of sufficiently high purity to
permit its use without lessening the accuracy of the determi-
nation.
6.2 Surfactants—Suggested surfactants are listed in Table 1
4,5,6
and footnotes 4 through 6.
7. General Dispersion Procedure
7.1 The general procedure for determining and achieving
proper dispersion is outlined in Fig. 1 and described in detail
below:
7.1.1 Place a test portion of the powder to be analyzed in a
beaker containing the carrier liquid, selected according to
7.1.2.
Reagent Chemicals, American Chemical Society Specifications , American
Chemical Society, Washington, DC. For suggestions on the testing of reagents not
listed by the American Chemical Society, see Analar Standards for Laboratory
Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia
and National Formulary,
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: B821 − 10 B821 − 10 (Reapproved 2016)
Standard Guide for
Liquid Dispersion of Metal Powders and Related
Compounds for Particle Size Analysis
This standard is issued under the fixed designation B821; 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*Scope
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.
2. Referenced Documents
2.1 ASTM Standards:
B243 Terminology of Powder Metallurgy
B430 Test Method for Particle Size Distribution of Refractory Metal Powders and Related Compounds by Turbidimetry
B761 Test Method for Particle Size Distribution of Metal Powders and Related Compounds by X-Ray Monitoring of Gravity
Sedimentation
B822 Test Method for Particle Size Distribution of Metal Powders and Related Compounds by Light Scattering
3. Terminology
3.1 Definitions—Definitions of powder metallurgy terms can be found in Terminology B243.
4. Significance and Use
4.1 The method of powder dispersion in a liquid has a significant effect on the results of a particle size distribution analysis.
The analysis will show a too-coarse, unstable, or nonrepeatable distribution if the powder has not been dispersed adequately. It is
therefore important that parties wishing to compare their analyses use the same dispersion technique.
4.2 This guide provides established powder dispersion techniques for certain materials and the means of deriving techniques for
materials not listed. It should be used by all parties performing liquid-dispersed particle size analysis of all of the materials covered
by this guide (see 1.1, 1.2, and 4.1).
4.3 This guide should be used in the preparation of powders for use in Test Methods B430, B761, and B822 and other
procedures that analyze metal powder particle size distributions in liquid-dispersed systems.
5. Apparatus
5.1 Microscope, suitable for observation of particles in the size range of 5 to 1000 μm.
5.2 Ultrasonic Probe, ⁄2 -in. (25.4-mm) tip, with the power level to be determined by this guide.
This guide is under the jurisdiction of ASTM Committee B09 on Metal Powders and Metal Powder Products and is the direct responsibility of Subcommittee B09.02
on Base Metal Powders.
Current edition approved Sept. 1, 2010Oct. 1, 2016. Published September 2010October 2016. Originally approved in 1992. Last previous edition approved 20072010 as
B821 – 02B821 – 10.(2007). DOI: 10.1520/B0821-10.10.1520/B0821-10R16.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
B821 − 10 (2016)
TABLE 1 Recommended Dispersion Procedures
Ultrasonic
Treatment
Carrier Surfactant
Material Surfactant
Liquid Concentration
Power
Type Time, min
Level, W
Chromium carbide water none . none . .
A
or
bath
25 5
B C
Copper water Tween 21 3–5 drops bath 80 1
B
Ferroalloys isopropyl alcohol Tween 21 10 % bath 80 1
B C
Iron/steel water Tween 21 3–5 drops bath 80 1
B C
Manganese sulfide water Tween 21 3–5 drops bath 80 1
Molybdenum water sodium hexametaphosphate 0.01 % probe 160 3
or
bath 80 10
A
or
bath
25 5
B C
Nickel water Tween 21 3–5 drops bath 80 1
Tantalum water sodium hexametaphosphate 0.01 % probe 160 3
or
bath 80 10
Tantalum carbide water sodium hexametaphosphate 0.01 % probe 160 3
or
bath 80 10
A
or
bath
25 5
Tungsten water sodium hexametaphosphate 0.01 % probe 160 3
or
bath 80 10
A
or
bath
25 5
Tungsten carbide water sodium hexametaphosphate 0.01 % probe 160 3
or
bath 80 10
A
or
bath
25 5
A
As described in Test Method B430.
B 6
Tween 21, chemically known as polyoxyethylene sorbitan monolaurate, is manufactured by Croda International PLC, and is available from various chemical suppliers.
C
Three to five drops Tween 21 in 30 to 50 mL water.
5.3 Ultrasonic Bath—Power level to be determined by this guide.
6. Reagents
6.1 Purity of Reagents—Reagent grade chemicals should be used in all tests. Unless otherwise indicated, it is intended that all
reagents should conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society. Other
grades may be used, provided it is first ascertained that the reagent is of sufficiently high purity to permit its use without lessening
the accuracy of the determination.
4,5,6
6.2 Surfactants—Suggested surfactants are listed in Table 1 and footnotes 4 through 6.
7. General Dispersion Procedure
7.1 The general procedure for determining and achieving proper dispersion is outlined in Fig. 1 and described in detail below:
7.1.1 Place a test portion of the powder to be analyzed in a beaker containing the carrier liquid, selected according to 7.1.2.
7.1.2 Selection of Carrier Liquid:
NOTE 1—The selected carrier liquid must be compatible with the components of the instrument used for the particle size analysis.
7.1.2.1 If the powder reacts with, or is soluble in, water and organic liquids, it must be analyzed in the dry state, and the
remainder of this guide is then not applicable.
7.1.2.2 If the powder reacts with, or is soluble in, water, but not organic liquids, select an appropriate organic liquid.
7.1.2.3 If the powder is neither reactive nor soluble in water, select distilled or deionized water as the carrier liquid.
Reagent C
...