The reverse impact test of color coated steel coil is used for evaluate the the ability of the sample’s coating to resist cracking or peeling when subjected to rapid deformation. The shock resistance also names impact strength, it means that the coating film applied to the sample endure the impact effect of the free fall of the heavy bob, the sample quickly deformed to form a convex area. The reverse impact test is used by CAMELSTEEL to test if the coating of convex area have craze or fall off, then to evaluate the coating ability of anti-cracking or shedding, and check the flexibility of the test coating and the adhesion to the substrate.
The instrument of reverse impact test is the impact tester, it’s the common instrument of this test. In accordance with the provisions of the National Standard GB / T 13448–2006, the punch diameter is 15.87 mm, and use the “qualified / failed” and “maximum impact” two ways to show the test results. The former with the tear tape method to check if the coating peel under the provisions of the hammer weight and drop the height of the impact, then use the magnifying glass observes whether the coating is cracked. The latter is by changing the weight of the hammer and drop the height of the impact, to find the maximum quality and maximum height that the coating does not produce cracking or stripping , and the product of the two as the maximum impact.