Usually 24-gauge thin metal panels (steel or aluminum) that are uniformly coated and cured.
The weight is dropped from a low height where no failure is expected.
Failure is defined by the appearance of cracks or delamination in the coating. Because these cracks can sometimes be microscopic, technicians use several methods for confirmation: impact test astm d2794
Once a crack is visible, the height is recorded. To ensure statistical accuracy, the test is typically repeated five times at that height, as well as at heights slightly above and below it. Evaluation and Failure Detection
A cylindrical weight (typically 2 lb or 4 lb) that falls through a vertical guide tube. Usually 24-gauge thin metal panels (steel or aluminum)
This poor reproducibility is a primary reason for withdrawal. Coatings sensitive to panel thickness or temperature show extreme lab-to-lab variation.
"Coating shall withstand 40 in·lb direct impact and 20 in·lb reverse impact without cracking or adhesion loss when tested per ASTM D2794 on 0.032 in steel panels." This poor reproducibility is a primary reason for withdrawal
The Impact Test ASTM D2794 provides valuable information on the performance of coatings and paints under conditions that simulate real-world impacts. The test results can help: