Physical and Mechanical Tests of Protective Coatings on Metal Surfaces

Abstract

This paper proposes a new method for estimating the elastic modulus of protective polymer coatings based on standard tensile tests on three-layer strip specimens. The proposed method derives the coating’s elastic modulus from a comparison of experimental elastic modulus values obtained for the base material (08 PS steel) and the effective elastic modulus for specimens coated with the studied coatings. The differences between these values are 10–15%. In this case, the accuracy of estimating the coating’s elastic modulus largely depends on the accuracy of stress and strain determination during testing of the material specimens, which were measured using ZWICK Z100 precision equipment and mechanical testing methods. Using this equipment, tensile tests were performed on four protective polymer coatings applied to the specimen surfaces. The elastic modulus values of the coatings were calculated using the rule of mixtures. For two modifications of the studied coatings, the elastic modulus values were obtained from four-point bending tests. It was shown that both methods yield similar values for the elastic modulus of the coatings.