Quickly identify whether galvanized steel sheet is dezincification

The essence of poor adhesion of the zinc layer is the poor bonding force between the galvanized layer and the steel substrate, which reflects the peeling of the zinc layer from the substrate after processing and deformation.

1. Cut the galvanized sheet into small strips about the width of the palm;

2. Fold the strip 180° in half using a bench vise. Be careful not to damage the corners;

3. Wipe the corners clean with alcohol cotton;

4. Use 3M scotch tape to stick the corners, calmly leave it for about 10 seconds, and quickly tear it off;

5. Observe whether the zinc flakes are peeled off at the corners of the steel plate and on the tape.

If the zinc flakes peel off and expose the substrate, it means that the zinc layer has poor adhesion