ASTM D3451-92

Standard Practices for Testing Polymeric Powders and Powder Coatings

SCOPE
1.1 This guide covers the selection and use of procedures for testing coating powders and powder coatings. The test methods included are listed in . Where more than one test method is listed for the same characteristic, no attempt is made to indicate superiority of one method over another. Selection of the methods to be followed must be governed by experience and the requirements in each individual case, together with agreement between the purchaser and the seller.
1.2 This guide also refers to methods developed specifically for the coating powder industry by the Powder Coating Institute, PCI, and the International Organization for Standards, ISO.
1.3 This guide describes the testing of coating powders as applied by electrostatic spray, fluidized bed, or any other applicable method.
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: 09-Feb-2001
• ICS: 87.040 - Paints and varnishes
• Technical Committee: D01 - Paint and Related Coatings, Materials, and Applications
• Drafting Committee: D01.51 - Powder Coatings

Relations

• Replaced By: ASTM D3451-01 - Standard Guide for Testing Coating Powders and Powder Coatings
• Effective Date: 10-Feb-2001
• Referred By: ASTM D6441-05(2016) - Standard Test Methods for Measuring the Hiding Power of Powder Coatings
• Effective Date: 10-Feb-2001
• Referred By: ASTM G195-22 - Standard Guide for Conducting Wear Tests Using a Rotary Platform Abraser
• Effective Date: 10-Feb-2001
• Referred By: ASTM D2832-92(2016) - Standard Guide for Determining Volatile and Nonvolatile Content of Paint and Related Coatings
• Effective Date: 10-Feb-2001
• Referred By: ASTM D5861-07(2017) - Standard Guide for Significance of Particle Size Measurements of Coating Powders
• Effective Date: 10-Feb-2001

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: D 3451 – 92
AMERICAN SOCIETY FOR TESTING AND MATERIALS
100 Barr Harbor Dr., West Conshohocken, PA 19428
Reprinted from the Annual Book of ASTM Standards. Copyright ASTM
Standard Practices for
Testing Polymeric Powders and Powder Coatings
This standard is issued under the fixed designation D 3451; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope D 659 Test Method for Evaluating Degree of Chalking of
Exterior Paints
1.1 These practices cover the selection and use of proce-
D 660 Test Method for Evaluating Degree of Checking of
dures for testing polymeric powders and powder coatings. The
Exterior Paints
test methods included are listed in Table 1. Where more than
D 661 Test Method for Evaluating Degree of Cracking of
one test method is listed for the same characteristic, no attempt
Exterior Paints
is made to indicate superiority of one method over another.
D 662 Test Method for Evaluating Degree of Erosion of
Selection of the methods to be followed must be governed by
Exterior Paints
experience and the requirements in each individual case,
D 714 Test Method for Evaluating Degree of Blistering of
together with agreement between the purchaser and the seller.
Paints
1.2 These practices describe the testing of polymeric pow-
D 772 Test Method for Evaluating Degree of Flaking (Scal-
ders as applied by electrostatic spray, fluidized bed, or any
ing) of Exterior Paints
other applicable method.
D 792 Test Methods for Specific Gravity (Relative Density)
1.3 These practices apply to proper and safe packaging,
and Density of Plastics by Displacement
shipping and receiving, and storage and handling during use
D 870 Practice for Testing Water Resistance of Coatings
and application of polymeric powders.
Using Water Immersion
1.4 This standard does not purport to address all of the
D 968 Test Methods for Abrasion Resistance of Organic
safety problems, if any, associated with its use. It is the
Coatings by Falling Abrasive
responsibility of the user of this standard to establish appro-
D 1005 Test Methods for Measurement of Dry-Film Thick-
priate safety and health practices and determine the applica-
ness of Organic Coatings Using Micrometers
bility of regulatory limitations prior to use.
D 1044 Test Method for Resistance of Transparent Plastics
2. Referenced Documents to Surface Abrasion
D 1186 Test Methods for Nondestructive Measurement of
2.1 ASTM Standards:
Dry Film Thickness of Nonmagnetic Coatings Applied to
B 117 Practice for Operating of Salt Spray (Fog) Testing
a Ferrous Base
Apparatus
D 1193 Specification for Reagent Water
D 153 Test Methods for Specific Gravity of Pigments
D 1308 Test Method for Effect of Household Chemicals on
D 522 Test Method for Mandrel Bend Test of Attached
Clear and Pigmented Organic Finishes
Organic Coatings
D 1400 Test Method for Nondestructive Measurement of
D 523 Test Method for Specular Gloss
Dry Film Thickness of Nonconductive Coatings Applied to
D 609 Practice for Preparation of Cold-Rolled Steel Panels
a Nonferrous Metal Base
for Testing Paint, Varnish, Conversion Coatings, and
D 1474 Test Methods for Indentation Hardness of Organic
Related Coating Products
Coatings
D 610 Test Method for Evaluating Degree of Rusting on
D 1535 Test Method for Specifying Color by the Munsell
Painted Steel Surfaces
System
D 658 Test Method for Abrasion Resistance of Organic
D 1644 Test Methods for Nonvolatile Content of Varnishes
Coatings by Air Blast Abrasive
D 1729 Practice for Visual Evaluation of Color Differences
of Opaque Materials
D 1730 Practices for Preparation of Aluminum and
These practices are under the jurisdiction of ASTM Committee D-1 on Paint
Aluminum-Alloy Surfaces for Painting
and Related Coatings, Materials, and Applications and are the direct responsibility
D 1731 Practices for Preparation of Hot-Dip Aluminum
of Subcommittee D01.51 on Powder Coatings.
Current edition approved May 15, 1992. Published July 1992. Originally
Surfaces for Painting
e1
published as D 3451–75. Last previous edition D 3451–76 (1987) .
Annual Book of ASTM Standards, Vol 03.02.
3 6
Annual Book of ASTM Standards, Vol 06.03. Annual Book of ASTM Standards, Vol 08.01.
4 7
Annual Book of ASTM Standards, Vol 06.01. Annual Book of ASTM Standards, Vol 11.01.
5 8
Annual Book of ASTM Standards, Vol 06.02. Annual Book of ASTM Standards, Vol 02.05.
D 3451
TABLE 1 List of Test Methods
Section ASTM Section ASTM
method method
Polymeric Powder Properties: Gravelometer 24 D 3170
Particle size and distribution 8 Color, pigmented coatings 25
Multiple sieve and analysis 8.1 D 1921 Visual 25.2 D 1535
Vacuum sieve analysis 8.2 Instrumental 25.3 E 308
Sonic sifter analysis 8.3 Color difference 26
Electronic counting analysis 8.4 Visual 26.2 D 1729
Package stability 9 Instrumental 26.2 D 2244
Glass vial method 9.1 Cracking resistance
Open dish method 9.2 Humidity, thermal cycle27 D 2246
Pourability10 D 1895 Elongation28
Fluidity11 Conical mandrel 28.2 D 522
Nonvolatile content12 D 1644 Cylindrical mandrel 28.2
Volatile content at fusion temperature 13.1 Filiform corrosion 29 D 2803
Gel time (stroke cure) 14 Film thickness
Melting point 15 On nonmagnetic metal 20.5 D 1400
Viscosity (Weissenberg) 16 On magnetic base 20.5 D 1186
Flow test (incline method) 17 Destructive method 20.5 D 1005
Density and specific gravity 18 Gloss 30 D 523
Apparent density 18.1 D 1895 Hardness 31
Bulk factor 18.2 D 1895 Knoop indentation 31.1 D 1474
Specific gravity 18.3 D 153 Pfund indentation 31.1 D 1474
Application Properties: Impact resistance 32 D 2794
Efficiency of powder coating process 19 Outdoor exposure 33
Powder Coating Properties: Blistering 33.2.1 D 714
Abrasion resistance 21 Chalking 33.2.2 D 659
Air blast abrasion tester D 658 Checking 33.2.3 D 660
Falling sand method D 968 Cracking 33.2.4 D 661
Taber abraser D 1044 Rusting 33.2.5 D 610
Adhesion Erosion 33.2.6 D 662
Scrape adhesion 22 D 2197 Flaking 33.2.7 D 772
Parallel groove D 2197 Print resistance 34 D 2091
Tape adhesion D 3359 Salt spray resistance 35 B 117
Chemical resistance 23 Water resistance 36
Household chemical resistance 23.2 D 1308 High humidity 36.2 D 1735
Detergent resistance 23.3 D 2248 Water immersion 36.3 D 870
Chip resistance Safety and Handling 37
D 1732 Practices for Preparation of Magnesium Alloy Sur- D 2803 Guide for Filiform Corrosion Resistance of Organic
8 4
faces for Painting Coatings on Metal
D 1735 Practice for Testing Water Resistance of Coatings D 3170 Test Method for Chipping Resistance of Coatings
Using Water Fog Apparatus D 3359 Test Methods for Measuring Adhesion by Tape
D 1895 Test Methods for Apparent Density, Bulk Factor, Test
and Pourability of Plastic Materials E 11 Specification for Wire-Cloth Sieves for Testing Pur-
6 9
D 1898 Practice for Sampling of Plastics poses
D 1921 Test Method for Particle Size (Sieve Analysis) of E 308 Method for Computing the Colors of Objects By
6 4
Plastic Materials Using the CIE System
D 2091 Test Method for Print Resistance of Lacquers
3. Terminology
D 2092 Guide for Preparation of Zinc-Coated (Galvanized)
Steel Surfaces for Painting
3.1 Definitions of Terms Specific to This Standard:
D 2197 Test Method for Adhesion of Organic Coatings by 3.1.1 bulk density—mass per unit volume of a material in
Scrape Adhesion
powder form including the air trapped between particles.
D 2201 Practice for Preparation of Zinc–Coated and Zin- 3.1.2 coating powder—finely divided particles of organic
c–Alloy–Coated Steel Panels for Testing Paint and Related polymer, either thermoplastic or thermosetting, which gener-
Coating Products
ally contain pigments, fillers, and additives and which remain
D 2244 Test Method for Calculation of Color Differences finely divided during storage under suitable conditions.
from Instrumentally Measured Color Coordinates
3.1.3 film formation from a coating powder—the forming of
D 2246 Test Method for Finishes on Primed Metallic Sub- a continuous film by melting powder particles and coalescing
strates for Humidity-Thermal Cycle Cracking
them by the application of energy.
D 2248 Practice for Detergent Resistance of Organic Fin- 3.1.3.1 Discussion—For thermosetting materials, a chemi-
ishes
cal reaction, either condensation or addition, also takes place.
D 2454 Practice for Determining the Effect of Overbaking For thermoplastic materials, no chemical reaction takes place.
on Organic Coatings
D 2794 Guide for Resistance of Organic Coatings to the
Effects of Rapid Deformation (Impact) Annual Book of ASTM Standards, Vol 14.02.
D 3451
The material flows when heat is applied and develops perfor- after conditioning 16 h unless otherwise specified.
mance properties when cooled. Flow will reoccur when re-
5. Sampling
heated. Both films have the uniformity of color, toughness, and
5.1 Sample the powder in accordance with Practice D 1898.
other properties associated with protective and decorative
5.2 Prepare specimens as required for the specific tests on
coatings. This fused film has the uniformity, color, toughness,
the coating.
and other properties associated with protective and decorative
coatings.
6. Equipment
3.1.4 fluidity—the ability of a powder to move freely,
6.1 Use the equipment as specified in each method of test.
uniformly, and continuously (somewhat like a liquid) when
subjected to certain conditions of pressure, temperature, and
7. Conditions Affecting Polymeric Powder or Powder
velocity of a carrier gas.
Coatings, or Both
3.1.5 gel time—interval required at a given temperature for
7.1 Practical requirements and performance of powder and
a powder to be transformed from a dry solid to a gel-like state.
powder coating may vary with:
3.1.6 particle size—average diameter of an object having
7.1.1 Substrate Type—Ferrous, nonferrous types, plastic, or
irregular boundaries that can be described in an artificial way
elastomeric.
as having a diameter.
7.1.2 Substrate Weathering—Weathering of the substrate
3.1.7 particle-size distribution—arrangement of particle
will probably adversely affect the performance.
size measurements on a powder in groups of specified diam-
7.1.3 The type, quality, and suitability of the metal treatment
eters.
or primer used under the powder coating and the time before
3.1.8 pourability—the ability of a powder to flow uniformly
coating application.
or to be continuously poured from a container at a steady rate.
7.1.4 Application conditions.
3.1.9 powder coatings—coatings which are protective or
7.1.5 Contaminants on the surface of the substrate.
decorative, or both, formed by the application of a coating
7.1.6 Damage to container, size of container, storage time,
powder (3.1.2) to a substrate and fused into a continuous film
excessive temperature, and temperature fluctuations which
by the application of heat or radiant energy.
may cause settling, caking, or chemical change.
3.1.10 storage stability—the ability of a powder to maintain
uniform physical and chemical properties after being subjected
POLYMERIC POWDER PROPERTIES
to specified storage conditions.
3.1.11 volatile content—the quantity expressed as weight
8. Particle Size and Distribution
percent of the powder which is lost under specified conditions
NOTE 1—Technology in particle size and distribution measurement,
of temperatures and time.
such as laser diffraction, has been developed. Instruments are commer-
3.1.12 cloud chamber technique—method of moving a
cially available from several suppliers.
charged or uncharged object through a charged or uncharged
8.1 Multiple Sieve Analysis:
cloud of powder in an enclosed chamber.
8.1.1 This method employs multiple sieves to determine
3.1.13 electrostatic deposition—technique of moving and
particle sizes and their distribution. Standard 200-mm (8-in.)
charging powder so that it is deposited onto an oppositely
diameter sieves and a mechanical shaker are used. A represen-
charged substrate by one of the following methods.
tative quantity of the sample is sifted through a series of sieves
3.1.14 fluidized bed technique—method of moving a
and the amount retained on each sieve is weighed and
grounded object over or through a charged fluidized powder.
calculated as percent of the total specimen.
3.1.15 spray technique—method of spraying and charging
8.1.2 Apparatus:
powder so that it is deposited onto a grounded charged
8.1.2.1 Sieves—Half-height sieves, 203.2 mm (8.0 in.) in
substrate.
diameter, conforming to the requirements of Specification
3.1.16 nonelectrostatic deposition—technique of moving
E 11. A selection of sieves encompassing the expected range of
powder onto a substrate which may be heated above the fusion
particle sizes together with a cover and a bottom pan are
point of the powdered material.
required.
3.1.17 spray technique—method of spraying powder onto a
8.1.2.2 Mechanical Sieve Shaker with Automatic Time
substrate which may be heated above the fusion point of the
Switch —The mechanical sieve-shaking device shall be ca-
powdered material.
pable of imparting uniform rotary motion and a tapping action
3.1.18 fluidized bed technique—method of dipping a hot
at the rate of 150 6 10 taps/min.
object into a container holding the powder suspended in a gas
8.1.2.3 Balance—A laboratory balance with a minimum
stream so that it resembles a fluid and allowing the powder to
capacity of 500 g sensitive to 0.1 g, for weighing the specimen
melt onto the object being coated.
and the residues retained on the sieves.
3.1.19 flame spread technique—method of applying powder
8.1.3 Procedure:
using a compressed gas and melting the powder in a flame
8.1.3.1 If the residues are not to be transferred for weighing,
before the powder impinges on the surface.
weigh each of the selected sieves and the bottom pan to 0.1 g.
4. General Requirements
4.1 All tests shall be made in diffused light (not direct
Ro-Tap Sieve Shaker has been found suitable for this purpose and is available
sunlight) and at 23 6 2°C and 50 6 5 % relative humidity, from W. S. Tyler Co., Cleveland, Ohio 44114. An equivalent may be used.
D 3451
Nest the desired sieves in order of diminishing openings with vice capable of maintaining inside the housing a vacuum of
the coarsest sieve on top and the pan on the bottom. 5 6 0.5 in. (127 6 12.7 mm) of water as measured by a
manometer. The slit nozzle which rotates below the sieve shall
8.1.3.2 Weigh out a 100 6 0.1-g specimen and tra
...