The test utilizes a specialized apparatus known as a variable-height impact tester. The process involves dropping a weighted indenter from a specific height onto a coated metal panel. The kinetic energy of the falling weight deforms both the coating and the substrate, creating a hemispherical indentation.
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In a reverse impact test, the weight strikes the of the panel directly. This forces the coating outward.
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The weight strikes the coated side (intrusion).