ASTM D1005 Standard Test Method for Measurement of Dry-Film Thickness of Organic Coatings Using Micrometers

Get Certified ASTM D1005 Testing for Reliable Dry-Film Thickness Evaluation

ASTM D1005 testing is a micrometric measurement used to determine the thickness of dried organic coating films. Procedure A uses stationary micrometers, while Procedure B uses hand-held micrometers, allowing engineers to measure coating thickness on rigid surfaces or free films under defined measurement conditions. The results may be used for the evaluation of paint, varnish, lacquer, and other coatings in coating development, quality control, and for comparison with specified thicknesses.

• Material type: Dried films of paint, varnish, lacquer, and related coating products.
• Purpose: Determination of dry-film thickness using micrometers.
• Primary property: Thickness of dried organic coating films.
• Measurement method: Stationary or hand-held micrometer measurement.
• Procedure A: Stationary micrometer for coatings applied to plane rigid surfaces.
• Procedure B: Stationary micrometer for free films.
• Procedure C: Hand-held micrometer for coatings applied to plane rigid surfaces.
• Procedure D: Hand-held micrometer for free films.
• Thickness limitation: Procedures A and C are not recommended for films less than 12.5 μm (0.5 mil) in thickness.
• Free-film limitation: The minimum thickness for Procedures B and D depends on the thickness required to remove the sample as a free film.
• Measurement units: SI units are regarded as the standard measurement basis.

What are the Uses of ASTM D1005 Testing?

ASTM D1005 testing determines the thickness of dried organic coating films on rigid surfaces or as free films. Therefore, the results may help engineers assess coating application, uniformity, and performance. The ASTM D1005 standard:

• Measures the thickness of dried organic coating films.
• Evaluates coatings on plane rigid surfaces.
• Determines the thickness of free coating films.
• Assists in testing paint, varnish, lacquer, and other products.
• Assists in the evaluation of coating thicknesses on laboratory test panels.
• Helps in the comparison of coating thicknesses for various specimens.
• Assists with quality control assessments of coatings.
• Assists in determining the thickness of the coating and whether it complies with the relevant requirements.
• Provides thickness information for coating performance and development.
• Compares measurements made with appropriate static or hand-held micrometers.

Which materials can be tested under ASTM D1005?

ASTM D1005 applies to dried films of paint, varnish, lacquer, and other coating products that may be measured with a micrometer. If the coating is applied to a plane rigid surface or is prepared as a free film, the appropriate procedure can be chosen based on the configuration of the specimen. The coating should not be easily deformable under the measuring load, as deformability can affect the accuracy and precision of the thickness measurement.

Why is ASTM D1005 Important?

ASTM D1005 is significant because dry film thickness is directly related to assessing coating application and performance. When coatings are applied to laboratory test panels, coating deformability and substrate uniformity can affect coating thickness measurements. The standard has clearly specified procedures for stationary and hand-held micrometers and for rigid-surface coatings and free films. Engineers can therefore use the results to assess coating thickness and the choice of supporting material, develop the coating, perform quality control, and evaluate coating performance. However, the coating deformability will make a big difference in the thickness measured. Substrate uniformity and the coating condition during measurement can also affect the measured response.

ASTM D1005 Testing Process and Data Collection

ASTM D1005 testing starts with selecting and preparing a dried coating specimen appropriate for the selected measurement procedure. The specimen is then set for measurement, and the needed stationary or hand-held micrometer is set up. The coating thickness is measured at representative points without excessive deformation of the coating by the technician. In free-film measurements, the film is carefully removed but not altered in thickness. The measuring system then stores the thickness values, and the measured values describe the dry-film thickness of the coating under the selected measurement conditions; the coating thickness can be compared between the specimens if the coating was measured by the same procedures and conditions.

Common Challenges and Troubleshooting

Coating conditions, specimen preparation, instrument selection, and contact with the specimen all affect accurate ASTM D1005 results. The thickness of coatings that are prone to deformation under the force of the micrometer can be difficult to measure, since deformation can cause errors in the thickness measurement and decrease measurement accuracy and precision. When laboratory test panels are coated, uniformity of the substrate should also be taken into account. Thus, proper measurement methods should be used, and distortion should be avoided during the instrument’s positioning. A major concern is the preparation of free films, because the film may be stretched or otherwise damaged and cause the measured thickness to be different. Therefore, it is important that the test team keep the specimen and measuring instrument in the same condition as much as possible during the measurement period.

• The laboratory records coating thickness and measurement information to determine the dry-film thickness response.
• The analyst uses the thickness readings to determine the uniformity of the coating at the locations measured.
• The laboratory reports results in μm and includes a mils equivalent when necessary, and includes the ASTM D1005 procedure used.
• Engineers compare the thickness of the coating between specimens subjected to the same measurement procedure and under the same conditions.
• Analysts use the recorded results to support coating evaluation, product development, quality control, specification assessment, and coating performance evaluation.

Link to ASTM D1005