This method allows to evaluate the resistance of the dry paint film or product related to cracking, when it is subjected to a deformation caused by a falling load at standard conditions. The purpose of the test is to determine the impact energy of the falling load, causing the first cracking on the sample surface. No special procedure is generally required for powdered products, but unusual features must be recorded, such as the abnormal color, the presence of large or rough lumps, the presence of unrelated bodies, etc.. Generally, the sample to be tested is obtained by mixing the powder with a liquid solution. The substrate must be of concrete or otherwise of a rigid, planar material, free of distortion and of at least 0.25 mm thickness. The dimensions must be such as to enable the test to be at least five different positions of not less than 40 mm apart and not less than 20 mm from the edge of the panel. After preparing the samples, these are to be completed at temperature of (23 ± 2)°C and a relative humidity of (50 ± 5)% for at least 16 h. Perform the test, ensuring that the guide tube is vertical. Adjust the height of the primary load to the position where it is expected that there is no any rupture and lock into place. Put a test panel on the stump with the coated face upwards. Hold the test panel in place with the clamping sleeve. Release the load and drop it on the test panel. Remove the test panel from the apparatus and examine the area deformed in order to identify cracks on the coating and/or delamination on the substrate. If no cracks and/or visible delaminations, repeat the process in succession to greater heights until cracks are observed and/or denominations. The height increments should be 25 mm or multiples of 25 mm, going to adjust the height in which are observed cracks and/or delaminations for the first time. If you observe cracks and/or delaminations when the load is dropped from the maximum height allowed by the apparatus, repeat the operation with an additional secondary load, for a total of 2, 3 or maximum 4 kg. When you find the right load, dropping it five times in different positions of the test panel, the height where the first cracks have been identified, 25 mm above and 25 mm below this height. Scoring as the end point of the test, the combination of mass/height for which are obtained appreciable values ​​in terms of cracks or damage of the material. The results are expressed as the impact energy (N * m), knowing the falling load and the height that determines the breakage or detachment of the sample.

 

Material type Standard Test method
screeds EN 13813 EN ISO 6272
self-levelings EN 13813 EN ISO 6272
grouting mortars EN 13888
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waterproofing EN 14891
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paints/varnishes - EN ISO 6272
surface protection mortars EN 1504-2 EN ISO 6272

 

Instruments used to perform the test: Impact resistance tester

 

This method allows to evaluate the resistance of dry paint film or the resistance of product related to cracking, when it is subjected to a deformation.This method allows to evaluate the resistance of dry paint film or the resistance of product related to cracking, when it is subjected to a deformation.