GB/T 30789.4-2015 "Paints and varnishes—Evaluation of degradation of coatings—Designation of quantity and size of defects, and of intensity of uniform changes in appearance—Part 4: Assessment of degree of cracking" is applicable to the grading of cracking defects in coatings after aging. It involves simulating natural aging environments using aging test chambers, followed by observation of coating cracks using magnifying glasses or stereomicroscopes. The assessment is conducted by comparing the characteristics of cracks, such as density, width, and depth, against standardized grading rules. The method specifies requirements for observation angles, magnification, and other parameters, providing a standardized approach for evaluating the aging performance of coatings.
| Status | Active | ||
|---|---|---|---|
| CCS | G50 | ICS | 87.040 |
| Release Date | 2015-07-03 00:00:00 | Implementation Date | 2016-02-01 00:00:00 |
