ASTM B212-21

Standard Test Method for Apparent Density of Free-Flowing Metal Powders Using the Hall Flowmeter Funnel

SIGNIFICANCE AND USE
5.1 This test method provides a guide for evaluation of an important physical characteristic of a powder known as the apparent density. The measured apparent density bears a relationship to the mass of powder that will fill a fixed volume die cavity. The degree of correlation between the results of this test and the performance of powders during use may vary with each particular application. Note, however, that the presence of moisture, oils, stearic acid, stearates, waxes, and the temperature of the powder mass may alter the physical characteristics of the powder.
SCOPE
1.1 This test method describes a procedure for determining the apparent density of free-flowing metal powders, and mixed powders; and is suitable for only those powders that will flow unaided through the specified Hall Flowmeter funnel.  
1.2 Units—With the exception of the values for mass, volume, and density, for which the use of the gram and the cubic centimetre units is the long-standing industry practice, the values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered 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.

General Information

• Status: Published
• Publication Date: 31-Aug-2021
• ICS: 77.160 - Powder metallurgy
• Technical Committee: B09 - Metal Powders and Metal Powder Products
• Drafting Committee: B09.02 - Base Metal Powders

Relations

• Refers: ASTM E456-13a(2022)e1 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 01-Apr-2022
• Refers: ASTM B243-18 - Standard Terminology of Powder Metallurgy
• Effective Date: 01-Oct-2018
• Refers: ASTM E456-13A(2017)e1 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 01-Oct-2017
• Refers: ASTM E456-13A(2017)e3 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 01-Oct-2017
• Refers: ASTM B243-16 - Standard Terminology of Powder Metallurgy
• Effective Date: 01-Jul-2016
• Refers: ASTM E456-13ae1 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 15-Nov-2013
• Refers: ASTM E456-13ae2 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 15-Nov-2013
• Refers: ASTM E456-13ae3 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 15-Nov-2013
• Refers: ASTM E456-13a - Standard Terminology Relating to Quality and Statistics
• Effective Date: 15-Nov-2013
• Refers: ASTM B243-13 - Standard Terminology of Powder Metallurgy
• Effective Date: 01-Nov-2013
• Refers: ASTM E456-13 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 15-Aug-2013
• Refers: ASTM E691-13 - Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
• Effective Date: 01-May-2013
• Refers: ASTM B873-12 - Standard Test Method for Measuring Volume of Apparent Density Cup Used in Test Methods B212, B329, and B417
• Effective Date: 01-Nov-2012
• Refers: ASTM B243-12 - Standard Terminology of Powder Metallurgy
• Effective Date: 15-Jul-2012
• Refers: ASTM E456-12 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 01-May-2012

Overview

ASTM B212-21: Standard Test Method for Apparent Density of Free-Flowing Metal Powders Using the Hall Flowmeter Funnel is a widely recognized method developed by ASTM International. This standard outlines a precise procedure for measuring the apparent density of free-flowing metal powders and mixed powders. Using the Hall Flowmeter Funnel, this test is crucial in quality control and material evaluation for various powder metallurgy and metal powder fabrication processes. Accurate determination of apparent density helps predict how powders will behave during compaction and forming, making this test essential in industries that rely on metal powders for manufacturing.

Key Topics

• Apparent Density Measurement: Defines the measured mass per unit volume of metal powders that can freely flow, reported as the Hall apparent density.
• Test Applicability: Specifically designed for powders that can flow unaided through the Hall Flowmeter funnel, ensuring uniformity in testing conditions.
• Test Method Overview: A defined volume of powder is allowed to flow into a density cup, and the resulting mass is used to calculate the apparent density.
• Apparatus Requirements: Utilizes a calibrated Hall Flowmeter funnel, a cylindrical brass density cup, a stable support stand, and a high-precision balance.
• Precision and Repeatability: Provides details on expected limits for repeatability and reproducibility to ensure high confidence in test results.
• Units of Measurement: Follows industry practice of using grams and cubic centimetres for mass, volume, and density, with SI conversions provided for reference only.
• Best Practice Cautions: Highlights the influence of moisture, oils, temperature, and other contaminants on powder properties, emphasizing the need for proper handling and environmental controls.

Applications

The ASTM B212-21 test method is vital in several practical applications within the metal powder industry:

• Powder Metallurgy: Used extensively to assess the quality of powders for pressing and sintering processes, directly influencing product performance and consistency.
• Quality Control: Enables manufacturers to verify batch-to-batch uniformity, ensuring powders meet specified standards before use in production.
• R&D and Material Development: Provides key data to optimize powder formulations and manufacturing processes, facilitating the development of improved materials and components.
• Sintered Component Manufacturing: Assists in predicting compaction characteristics and helps avoid issues with density variation in finished parts.
• Supplier and Buyer Agreements: Serves as an industry-standard reference point in transactions and evaluations between powder suppliers and end-users.

Related Standards

A number of other ASTM standards are commonly referenced in conjunction with ASTM B212-21 for comprehensive powder characterization and testing:

• ASTM B215: Practices for Sampling Metal Powders - Guidance on sampling procedures to ensure representative testing.
• ASTM B243: Terminology of Powder Metallurgy - Standard definitions for powder metallurgy processes and materials.
• ASTM B873: Test Method for Measuring Volume of Apparent Density Cup - Ensures accurate cup volume measurement for use with this and related test methods.
• ASTM E456: Terminology Relating to Quality and Statistics - Standard statistical terminology for quality control and reporting.
• ASTM E691: Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method - Methodology for precision analysis in test procedures.

Summary

ASTM B212-21 provides an essential, standardized procedure for determining the apparent density of free-flowing metal powders using the Hall Flowmeter Funnel. Reliable apparent density measurements help manufacturers maintain strict quality control, improve manufacturing processes, and ensure the performance of powder metallurgy products. For optimal results, use ASTM B212-21 in conjunction with related industry standards to achieve thorough and accurate evaluation of metal powders for industrial applications.

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: B212 − 21
Standard Test Method for
Apparent Density of Free-Flowing Metal Powders Using the
Hall Flowmeter Funnel
This standard is issued under the fixed designation B212; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope* E691 Practice for Conducting an Interlaboratory Study to
Determine the Precision of a Test Method
1.1 This test method describes a procedure for determining
the apparent density of free-flowing metal powders, and mixed
3. Terminology
powders; and is suitable for only those powders that will flow
3.1 Definitions—For definitions of terms used in this test
unaided through the specified Hall Flowmeter funnel.
method, see Terminology B243. Additional descriptive PM
1.2 Units—With the exception of the values for mass,
information is available under “General Information on PM”
volume, and density, for which the use of the gram and the
on the ASTM B09 web page.
cubic centimetre units is the long-standing industry practice,
the values stated in inch-pound units are to be regarded as
4. Summary of Test Method
standard. The values given in parentheses are mathematical
4.1 Avolumeofpowderispermittedtoflowintoacontainer
conversions to SI units that are provided for information only
of definite volume under controlled conditions. The mass of
and are not considered standard.
powderperunitvolumeisdeterminedandreportedasapparent
1.3 This standard does not purport to address all of the
density, Hall (AD ).
H
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
5. Significance and Use
priate safety, health, and environmental practices and deter-
5.1 This test method provides a guide for evaluation of an
mine the applicability of regulatory limitations prior to use.
important physical characteristic of a powder known as the
1.4 This international standard was developed in accor-
apparent density. The measured apparent density bears a
dance with internationally recognized principles on standard-
relationship to the mass of powder that will fill a fixed volume
ization established in the Decision on Principles for the
die cavity.The degree of correlation between the results of this
Development of International Standards, Guides and Recom-
test and the performance of powders during use may vary with
mendations issued by the World Trade Organization Technical
each particular application. Note, however, that the presence of
Barriers to Trade (TBT) Committee.
moisture, oils, stearic acid, stearates, waxes, and the tempera-
ture of the powder mass may alter the physical characteristics
2. Referenced Documents
of the powder.
2.1 ASTM Standards:
B215 Practices for Sampling Metal Powders
6. Apparatus
B243 Terminology of Powder Metallurgy
6.1 Powder Flowmeter Funnel —A calibrated Hall Flow-
B873 Test Method for Measuring Volume ofApparent Den-
meter funnel (Fig. 1).
sity Cup Used in Test Methods B212, B329, and B417
6.1.1 The funnel shall be made of a non-magnetic,
E456 Terminology Relating to Quality and Statistics
corrosion-resistantmetallicmaterialhavingsufficientthickness
and hardness to withstand distortion and excessive wear.
This test method is under the jurisdiction of ASTM Committee B09 on Metal
6.2 Density Cup—A cylindrical brass cup (Fig. 2) having a
Powders and Metal Powder Products and is the direct responsibility of Subcom-
nominal capacity of 25 cm . The actual cup volume shall be
mittee B09.02 on Base Metal Powders.
Current edition approved Sept. 1, 2021. Published September 2021. Originally
approved in 1946. Last previous edition approved in 2017 as B212 – 17. DOI:
10.1520/B0212-21. The sole source of supply of the apparatus known to the committee at this time
For referenced ASTM standards, visit the ASTM website, www.astm.org, or isACuPowder International, LLC, 901 LehighAve., Union, NJ 07083-7632. If you
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM are aware of alternative suppliers, please provide this information to ASTM
Standards volume information, refer to the standard’s Document Summary page on International Headquarters. Your comments will receive careful consideration at a
the ASTM website. meeting of the responsible technical committee, which you may attend.
*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
B212 − 21
FIG. 1 Flowmeter Apparatus — Hall Funnel
FIG. 2 Density Cup (25 6 0.03 cm )
determined according to Test Method B873. If the measured 6.3 Stand —Astand (Fig. 1) to support the Hall Flowmeter
volume of the cup is outside the tolerance in Fig. 2 funnelconcentricwiththedensitycupsothatthebottomofthe
(25 6 0.03 cm ) the cup shall not be used. Hall Flowmeter funnel orifice is approximately 1 in. (25 mm)
...

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: B212 − 17 B212 − 21
Standard Test Method for
Apparent Density of Free-Flowing Metal Powders Using the
Hall Flowmeter Funnel
This standard is issued under the fixed designation B212; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope*
1.1 This test method describes a procedure for determining the apparent density of free-flowing metal powders, and mixed
powders; and is suitable for only those powders that will flow unaided through the specified Hall Flowmeter funnel.
1.2 Units—With the exception of the values for mass, volume, and density, for which the use of the gram and the cubic centimetre
units is the long-standing industry practice, the values stated in inch-pound units are to be regarded as standard. The values given
in parentheses are mathematical conversions to SI units that are provided for information only and are not considered 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 safety, health, and healthenvironmental 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.
2. Referenced Documents
2.1 ASTM Standards:
B215 Practices for Sampling Metal Powders
B243 Terminology of Powder Metallurgy
B873 Test Method for Measuring Volume of Apparent Density Cup Used in Test Methods B212, B329, and B417
E456 Terminology Relating to Quality and Statistics
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
3. Terminology
3.1 Definitions—For definitions of terms used in this test method, see Terminology B243. Additional descriptive PM
information is available in the Related Materials section of Vol. 02.05 of the Annual Book of ASTM Standards.under “General
Information on PM” on the ASTM B09 web page.
This test method 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 April 1, 2017Sept. 1, 2021. Published April 2017September 2021. Originally approved in 1946. Last previous edition approved in 20132017 as
B212 – 13.B212 – 17. DOI: 10.1520/B0212-17.10.1520/B0212-21.
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
B212 − 21
4. Summary of Test Method
4.1 A volume of powder is permitted to flow into a container of definite volume under controlled conditions. The mass of powder
per unit volume is determined and reported as apparent density, Hall (AD ).
H
5. Significance and Use
5.1 This test method provides a guide for evaluation of an important physical characteristic of a powder known as the apparent
density. The measured apparent density bears a relationship to the mass of powder that will fill a fixed volume die cavity. The
degree of correlation between the results of this test and the performance of powders during use may vary with each particular
application. Note, however, that the presence of moisture, oils, stearic acid, stearates, waxes, and the temperature of the powder
mass may alter the physical characteristics of the powder.
6. Apparatus
6.1 Powder Flowmeter Funnel —A calibrated Hall Flowmeter funnel (Fig. 1).
6.1.1 The funnel shall be made of a non-magnetic, corrosion-resistant metallic material having sufficient thickness and hardness
to withstand distortion and excessive wear.
FIG. 1 Flowmeter Apparatus — Hall Funnel
The sole source of supply of the apparatus known to the committee at this time is ACuPowder International, LLC, 901 Lehigh Ave., Union, NJ 07083-7632. If you are
aware of alternative suppliers, please provide this information to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of the
responsible technical committee, which you may attend.
B212 − 21
6.2 Density Cup—A cylindrical brass cup (Fig. 2) having a nominal capacity of 25 cm . The actual cup volume shall be determined
according to Test Method B873. If the measured volume of the cup is outside the tolerance in is outside the tolerance in Fig.
(25 6 0.03 cm ) the cup shall not be used.
6.3 Stand —A stand (Fig. 1) to support the Hall Flowmeter funnel concentric with the density cup so that the bottom of the Hall
Flowmeter funnel orifice is approximately 1 in. (25 mm) above the top of the density cup when the apparatus is assembled as
shown in Fig. 1.
6.4 Workbench—A level, vibration-free table or workbench to support the powder flowmeter stand.
6.5 Balance—A balance, readable to 0.001 g, having a capacity of at least 200 g capable of determining the mass to the ne
...