[Professional] Cross-Cut Test

In surface treatment processes, plating or coatings are added to metal surfaces to increase surface hardness or enhance surface finish. However, after the finished product leaves the factory, plating peels off, affecting the overall reliability of the product. To avoid this, the "Cross-Cut Test" can be used to inspect the coating's coverage on the material.

Next, we will explain the "Cross-Cut Test" to help you better understand its importance.

Principle of the Cross-Cut test

First, we use a cutting tool to make cross-cuts on the surface of the plated workpiece (as shown in the picture above). During this process, the cutting depth should reach the surface of the material as much as possible. This way, when manually peeling off the tape later, we can clearly measure the adhesion between the plating layer and the surface of the material.

After cutting, apply the designated test tape (green indicator) to the plating layer and press it firmly onto the surface. Then peel the tape off the workpiece. Two results will appear:

• Normal Situation (Top Right Image)

• If no plating is removed from the cut area after the tape is peeled off, it indicates that the plating is perfectly applied to the material.
• Abnormal Situation (Bottom Right Image)
• If several areas of plating are noticeably peeled off at the cut point after the tape is peeled off (red circle indicator), it is highly likely that the workpiece was contaminated with dirt before the process (orange area in the image above), and the dirt was not removed after pretreatment cleaning before being directly placed in the electroplating tank.

Cutting type of the Cross-Cut test

Selection of test tape

The Cross-cut Test uses 3M 600 tape because its adhesion is highly standardized, stable, and conforms to international standards (such as ASTM D3359).

• Highly Stable Adhesion: Initial tack and peel strength are precisely controlled, preventing significant variations between production batches and ensuring consistent test results.
• Conforms to International Standards: Widely specified or recommended by ASTM and other material testing standards, as well as IPC (Printed Circuit Board Council) for adhesion verification of coatings, inks, PCB gold fingers, and IC packages.
• Strong and Residue-Free Material: Utilizing UPVC (rigid polyvinyl chloride) backing and a special acrylic adhesive layer, it is resistant to deformation and breakage during stretching, and peels off cleanly and without residue, ensuring accurate interpretation of the peel rate.
• Perfect Size: The common 3/4-inch (approximately 19mm) width perfectly covers the standard scribed area, facilitating standardized vertical peeling operations on production lines and in laboratories.