How to identify genuine weathering steel plates

Different methods can be used according to the different stages of rusted steel plates:

1. When the steel plate is not rusted, the naked eye cannot distinguish between genuine weathering steel plates and ordinary hot-rolled steel plates.

1) You need to refer to the steel plant's warranty. The warranty can also ask the supplier to provide the original with the steel plant's red seal to avoid merchants selling inferior products as good ones. The materials of ordinary hot-rolled steel plates are Q235B, SPHC, etc.

2) Provide samples to professional third-party testing agencies to test whether the metal composition matches the warranty [This method can be used at any stage of rusting]

2. In the first stage of steel plate rusting (1-3 months outdoors), genuine weathering steel begins to grow small rust spots, while ordinary steel plates have loose rust spots, and some poorly treated rusting even have rust skin falling off;

3. In the second stage of steel plate rusting (4-8 months outdoors), genuine weathering steel has less rust water, and the rust spots are small and dense; ordinary steel plates have more rust water, and the rust spots are larger and thinner; ordinary steel plates have more rust columns and tear marks, and the bottom of the workpiece shows signs of blackening;

4. In the third stage of steel plate rusting (more than 8 months outdoors), genuine weathering steel has a clear and dense rust core layer, and the rust spots are tightly adhered to form a protective layer, which can hardly rust when wiped by hand; ordinary steel plates have more rust, and even the entire rust skin peels off and rusts through. Genuine weathering steel tends to be reddish brown, and ordinary steel plates tend to be dark black.