ASTM C925-09(2019)

Standard Guide for Precision Electroformed Wet Sieve Analysis of Nonplastic Ceramic Powders

SIGNIFICANCE AND USE
4.1 Both suppliers and users of pulverized ceramic powders will find this test method useful to determine particle size distributions for materials specifications, manufacturing control, development, and research.  
4.2 The test method is simple, although tedious, uses inexpensive equipment, and will provide a continuous curve with data obtained with standardized woven sieves.
SCOPE
1.1 This guide covers the determination of the particle size distribution of pulverized alumina and quartz for particle sizes from 45 to 5 μm by wet sieving.  
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.2.1 The only exception is in the Section 5, Apparatus, 5.1 where there is no relevant SI equivalent.  
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: 30-Sep-2019
• ICS: 81.060.10 - Raw materials
• Technical Committee: C21 - Ceramic Whitewares and Related Products
• Drafting Committee: C21.04 - Raw Materials

Relations

• Replaces: ASTM C925-09(2014) - Standard Guide for Precision Electroformed Wet Sieve Analysis of Nonplastic Ceramic Powders
• Effective Date: 01-Oct-2019
• Refers: ASTM E161-12 - Standard Specification for Precision Electroformed Sieves
• Effective Date: 01-Apr-2012
• Refers: ASTM E161-00(2010) - Standard Specification for Precision Electroformed Sieves
• Effective Date: 01-May-2010
• Refers: ASTM E161-00(2004) - Standard Specification for Precision Electroformed Sieves
• Effective Date: 01-Oct-2004
• Refers: ASTM E161-00 - Standard Specification for Precision Electroformed Sieves
• Effective Date: 10-Apr-2000
• Refers: ASTM E161-96 - Standard Specification for Precision Electroformed Sieves
• Effective Date: 10-Dec-1996

Overview

ASTM C925-09(2019), “Standard Guide for Precision Electroformed Wet Sieve Analysis of Nonplastic Ceramic Powders,” outlines a systematic approach for determining the particle size distribution of pulverized alumina and quartz within the range of 45 to 5 μm. Developed by ASTM International, this guide is crucial for both suppliers and users in the ceramics industry for assessing materials to meet specifications, manage manufacturing control, and support development and research activities.

Wet sieve analysis using precision electroformed sieves is a widely adopted method due to its straightforward nature, minimal equipment requirements, and ability to generate continuous, reliable particle size distribution curves. The process facilitates robust quality assurance for nonplastic ceramic powders, leveraging standardized procedures for data consistency.

Key Topics

• Scope of Method: Focused on wet sieving of nonplastic ceramic powders, particularly alumina and quartz, utilizing particle size ranges from 45 μm down to 5 μm.
• Test Apparatus: Use of 3-inch precision electroformed sieves (ranging from 45 to 5 μm) with necessary support equipment, such as filtering flasks, Büchner funnels, vacuum sources, ultrasonic cleaners, analytical balances, and drying ovens.
• Sample Preparation: Emphasis on accurate sample reduction techniques to prevent segregation and ensure representative analysis.
• Wet Sieving Procedure: Step-by-step instructions for preparing, dispersing, sieving, washing, and weighing samples, including recommendations for repeated ultrasonic cleaning in fine sieving (≤20 μm).
• Data Reporting: Calculation and documentation guidelines for reporting particle size distributions, including weight percent greater than each aperture, aligned with SI units.
• Reproducibility: Recommendations for triplicate replications to ensure repeatability and reliability of results.
• Safety Guidance: Users are responsible for addressing safety, health, and environmental considerations before application.

Applications

ASTM C925 is broadly applied in quality control and R&D laboratories within the ceramics industry and related sectors:

• Materials Specification Compliance: Enables suppliers and manufacturers to verify particle size distributions against technical requirements and customer specifications.
• Process Control: Supports ongoing monitoring and adjustment of milling or grinding operations, ensuring consistent final product characteristics in ceramics manufacturing.
• Product Development and Research: Assists in optimizing formulations and performance attributes by providing detailed particle size insights.
• Supply Chain Assurance: Fosters mutual confidence between suppliers and customers through standardized, universally recognized measurement protocols.
• Academic Use: Serves as a reliable reference method for research projects and technical education regarding particle size analysis techniques.

Related Standards

For comprehensive compliance and best practices in particle size distribution analysis and the use of sieves, the following standards are also relevant:

• ASTM E161 - Specification for Electroformed Material and Test Sieves
  • Covers requirements for materials and calibration of precision sieves used in wet and dry particle size analysis.
• ASTM C21 - Whitewares and Related Products
  • The committee responsible for standards relating to ceramic raw materials and products.
• ASTM E11 - Specification for Woven Wire Test Sieve Cloth and Test Sieves
  • Often referenced for alternative sieving media and general requirements in particulate analysis.

Summary

ASTM C925-09(2019) delivers a robust, accessible protocol for precision wet sieve analysis of nonplastic ceramic powders, empowering ceramics professionals with standardized methods to assess, monitor, and ensure material quality. Its focus on SI units, safety, and international recognition underpins its reliability for global industry use. For further insight or expanded applications, integrating related ASTM standards is recommended.

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: C925 − 09 (Reapproved 2019)
Standard Guide for
Precision Electroformed Wet Sieve Analysis of Nonplastic
Ceramic Powders
This standard is issued under the fixed designation C925; 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* 4. Significance and Use
4.1 Both suppliers and users of pulverized ceramic powders
1.1 This guide covers the determination of the particle size
will find this test method useful to determine particle size
distribution of pulverized alumina and quartz for particle sizes
distributions for materials specifications, manufacturing
from 45 to 5 µm by wet sieving.
control, development, and research.
1.2 The values stated in SI units are to be regarded as
4.2 The test method is simple, although tedious, uses
standard. No other units of measurement are included in this
inexpensive equipment, and will provide a continuous curve
standard.
with data obtained with standardized woven sieves.
1.2.1 The only exception is in the Section 5,Apparatus, 5.1
where there is no relevant SI equivalent.
5. Apparatus
1.3 This standard does not purport to address all of the
5.1 Precision Electroformed Sieves , 3-in., mounted in brass
safety concerns, if any, associated with its use. It is the
frames, having nominal apertures of 45, 30, 20, 10, and 5 µm
responsibility of the user of this standard to establish appro-
andasupportgridhaving5.7linespercentimetre.Intermediate
priate safety, health, and environmental practices and deter-
sizes may also be used.
mine the applicability of regulatory limitations prior to use.
5.2 Sieving Device (Fig. 1):
1.4 This international standard was developed in accor-
5.2.1 Filtering Flask (suction flask), 1-L, with side arm,
dance with internationally recognized principles on standard-
5.2.2 Büchner Funnel (for example, Coors No. 2),
ization established in the Decision on Principles for the
5.2.3 O-Ring, 7.5-cm, rubber,
Development of International Standards, Guides and Recom-
5.2.4 Graduate, 1-L,
mendations issued by the World Trade Organization Technical
5.2.5 Rubber Stoppers, one-hole to fit the flask and the
Barriers to Trade (TBT) Committee.
funnel, two-hole to fit the graduate,
5.2.6 Quantity of glass tubing and rubber tubing,
2. Referenced Documents
5.2.7 Metal Rod, 15 to 20-cm, about 5 mm in diameter, and,
2.1 ASTM Standards: 5.2.8 Vacuum Source.
E161 Specification for Electroformed Material and Test
5.3 Ultrasonic Cleaner, required to clean all sieves below
Sieves
20 µm. It should be low-powered (for example, 100 W).
5.4 AnalyticalBalance,capableofweighingupto100gand
3. Summary of Guide
having at least three significant digits after the decimal.
3.1 A separate dispersed suspension of the powder is wet
5.5 Drying Oven, capable of maintaining 110 6 5 °C.
sieved through each sieve, using vacuum and vibration. The
5.6 Desiccator, containing magnesium perchlorate or other
sieve and sample are dried and weighed.
suitable desiccant.
6. Reagents and Materials
This guide is under the jurisdiction of ASTM Committee C21 on Ceramic
6.1 Water, visually clear and particle free, not necessarily
Whitewares and Related Productsand is the direct responsibility of Subcommittee
distilled, at room temperature or slightly above.
C21.04 on Raw Materials.
Current edition approved Oct. 1, 2019. Published October 2019. Originally
6.2 Sieving Solution, a dispersing media consisting of 0.1
approved in 1979. Last previous edition approved in 2014 as C925 – 09 (2014).
weight % solution of sodium hexametaphosphate or sodium
DOI: 10.1520/C0925-09R19.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or pyrophosphate in water.
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
6.3 Drying Agents, acetone or methyl alcohol, commercial
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. grade.
*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
C925 − 09 (2019)
within the quoted 2-µm tolerance. The calibration procedure is
given in Appendix X1 of Specification E161.
10. Procedure
10.1 Wash the sieves with the sieving solution, rinse with
water and then with the drying agent, dry at 110 °C for 15 min,
cool in the desiccator, and weigh to at least the nearest 1 mg.
10.2 Sample Size is somewhat dependent upon density, but
the following schedule is satisfactory for alumina and quartz:
Nominal Sieve Sample Weight
Apertures, µm (approximate), g
45, 30, 20 1.0
15, 10 0.4
5 0.15
10.3 Weigh the required amount of sample into a 100-mL
beaker, fill half with sieving solution (containing the dispersing
agent), and disperse by placing beaker in ultrasonic bath for 1
min. Microscopical examination of the particles after disper-
sion may be helpful in determining if the dispersion is
complete.
10.4 Wash the dispersed sample onto the sieve using a wash
bottle containing the sieving solution, turn on vacuum
...