How to detect film crazing?

Paint film crack is a representative damage phenomenon of paint film in use. Common cracks include strip cracks, fork cracks, network cracks, double cracks, bending cracks and other irregular cracks. To describe the severity of cracks in words, the method is as follows:

(1) Describe the shape of the crack in words.

(2) According to the depth of cracks, it can be divided into mild cracks (invisible to the eyes, but visible under a four-fold magnifying glass), moderate cracks (visible to the eyes, but not too obvious), and deep cracks (visible to the eyes). Obviously visible) and severe graining (cracks deep to the bottom layer, that is, primer or bottom plate).

(3) Evaluated according to the distribution area of ​​cracks, expressed as a percentage of the sample.

(4) Evaluated according to the density, that is, dense (indicated by D), relatively dense (indicated by MD), medium (indicated by M), and sparse (indicated by F).