[Film Properties and Measurements] - Determination of paint film adhesion

Paint film adhesion measurement is a method to evaluate the adhesion strength between coatings and substrates. It is mainly used to test the adhesion strength and stability of coatings on the surface of substrates.

Paint film adhesion measurement is usually tested by cross-cut method, disbonding method, Impact method and other methods. Among them, the cross-cut method is one of the commonly used methods. The cross-cut method measures the adhesion strength of the coating by engraving a grid of a certain shape and depth on the surface of the coating, and then using tape or special adhesion testing equipment for adhesion and disbonding. The disbonding law is to apply a specific disbonding force to the coating surface to measure the adhesion strength between the coating and the substrate. The Impact rule is to use Impact or impact on the surface of the coating to test the adhesion strength of the coating.

Paint film adhesion measurement can be used to evaluate the adhesion strength between various types of coatings and substrates, such as automotive paints, architectural coatings, metal coatings, etc. By measuring the adhesion strength between coatings and substrates, the stability and durability of coatings can be predicted, and basic data can be provided for formulating coating maintenance and improvement plans.

The following are two methods of film adhesion determination:

Cross-cut method: This is a simple and widely used paint film adhesion testing method. The specific steps are as follows:

(1) Use a blade or cross-cut instrument to scratch a cross-shaped pattern on the coating, and the scratch should penetrate the base material.

(2) Cover the score with tape, then tear off the tape, and observe whether the paint film is torn off, or whether there is obvious adhesion failure.

(3) According to the standard, the test results are divided into 0-5 grades to evaluate the adhesion of the paint film.

Disbonding test method: This is a more accurate paint film adhesion testing method. The specific steps are as follows:

(1) Use a special disbonding test instrument to disbond a small piece of coating off the substrate.

(2) According to the material properties and test requirements of the coating and substrate, select the disbonding speed and disbonding angle, and record the relevant data during the experiment.

(3) Calculate the adhesion value of the coating according to the test results.

NBchao reminds you: Different types of coatings and substrates may require different test methods and standards. In actual testing, appropriate test methods and standards should be selected according to the specific situation to obtain accurate and reliable test results.