Assessment of adhesion by grid method:

Classification Description

The edge of the 0 cut is smooth, without any squares falling off;

At the intersection of the incision, there is a slight separation of thin films in the coating, and the area of the grid is significantly affected by no more than 5%;

The detachment of the coating along the cutting edge or at the intersection of the incision is significantly greater than 5%, but the impact is significantly less than 15%;

The coating is partially or completely peeled off in large pieces along the cutting edge, or partially or completely peeled off at different parts of the grid

Falling, significantly greater than 15%, but the grid area is significantly affected by no more than 35%;

4. The coating peels off in large fragments along the cutting edge, or some grid parts and all peel off significantly more than 35%, but in the grid area

The impact is significantly less than 65%;

Even according to the fourth category, the degree of peeling cannot be identified;