How to distinguish weather resistant steel plate and ordinary steel plate?

When purchasing weather resistant steel plates and ordinary steel plates, what should be paid attention to, and what methods are there to distinguish the differences between weather resistant steel plates and ordinary steel plates?

1. The small rust spots of weather resistant steel plates are generally loose.

2. The weather resistant steel plate has less rust water, small and dense rust spots.

3. The weather-resistant steel plate has a clear high-density rust layer, and the rust spots are tightly adhered to the thickness of the protective layer, so that the rust will not drop at all when rubbed hard.

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