Adhesion Cross-Cut Testers

 

Electroplating, coating, and spraying industries use the 100 grid test to evaluate coating adhesion. Because of its easy operation and easy observation, it is widely used in the industry.

 

A scribe line is drawn to the depth of the substrate on the side object, and then the peeling area is used to test adhesion. A complete plating layer that completely peels off from the substrate after being adhered to the substrate by the tape, or only peels off from the substrate when scratched, indicates poor adhesion of the plating layer.

 

Test tape can be selected from the 600 series from 3M. Two test methods are described in ASTM D3359, "Standard Test Method for Measuring Adhesion-Tape Test Method," of the American Society for Testing and Materials. Method A is the X-cut method as shown in (2), and Method B is the cross-cut method as shown in (1).

Method A is used for coating systems with a thickness above 125 *m, and Method B is used for systems with a thickness less than 125 μm. Tests can be conducted on the job site as well as in the laboratory.

Originally, these two methods were used to evaluate the adhesion of the coating to steel, but they can also be used to evaluate the adhesion of other hard or soft substrates to the coating.

 

In order for the coating to function as a protective or decorative coating, it must be firmly adhered to the substrate and cannot fall off.

The substrate and its pretreatment have a great impact on the adhesion of the coating, so the test can quickly determine the degree of adhesion.

How are 100 grid tests performed? Holding the rubber grip (fingers cannot press the knife head), use a steady downward pressure to draw across the sample surface, and the knife head scrapes the coating off (onto the substrate).

Make a 90-degree cross cut to form a cross-shaped grid.

Tear off the standard tape at a steady speed, stick it to the cutting area, and press it tightly with your fingers to make it flat.

Within 1.5 minutes plus or minus 30 seconds, quickly tear off the tape at an angle of 180 degrees.

 

Check whether there is any film drop on the surface.

 

 

Use a magnifying glass to inspect the grid-like area on the sample surface to evaluate the adhesion of the coated surface.

 

 

Coating film adhesion evaluation result

 

 

SGS test report