1. Visual Inspection: Observe whether the coating is smooth and even, and whether there are defects such as bubbles, cracks, or peeling.
Check whether the color is uniform, paying special attention to weak areas such as corners and welds.
2. Thickness Measurement:
Measure the coating thickness using a dry film thickness gauge or a wet film thickness gauge to ensure it meets design requirements (such as ISO, ASTM standards).
Measure at multiple points (windward side, leeward side, welds, etc.), and calculate the average value and deviation.
3. Adhesion Test:
Cut-out test: Cut a grid with a knife, apply tape, and then peel it off to check if the coating peels off.
Pull-off test: Use specialized equipment to measure the coating peel strength.
4. Chemical Resistance and Weather Resistance Test:
Expose the specimen to acid, alkali, salt solutions or natural environments, and observe whether the coating changes color, blisters, or chalks.
5. Electrochemical and Salt Spray Testing
Evaluate corrosion resistance performance using electrochemical impedance spectroscopy (EIS).
Salt spray testing simulates a marine environment, observing corrosion pitting or blistering.
6. On-site Inspection
Regularly measure coating thickness and adhesion using portable instruments, recording changes in coating condition.
Precautions:
Clean the surface before testing to avoid dust and oil affecting the results.
The instrument needs regular calibration to ensure data accuracy.
