According to the different stages of rusted steel plates, different methods can be used: 1. At the stage when the weathering steel plates are not long rusted, the naked eye cannot distinguish between weathering steel plates and ordinary hot-rolled steel plates.
1. It is necessary to refer to the quality guarantee book of the weather-resistant steel plate factory. The quality guarantee book requires the weathering steel plate supplier to provide the original with the red seal of the steel factory as far as possible, so as to avoid the merchant from shoddy. The common materials of weathering steel plates are 09cupcrnia, B480GNQR, etc. of Baosteel or Anshan Iron and Steel, and the materials of ordinary hot-rolled steel plates are
q235b, SPHC, etc.
2. Provide weather-resistant steel plates for professional third-party testing to detect whether the metal composition matches the warranty certificate
In the rusting stage of weathering steel plate (1-3 months outdoors), the weathering steel plate begins to grow small rust spots, and the rust spots of ordinary steel plates are relatively loose, and some of the rust treatments are poor and even rust peeling; Third, the weathering steel plate is long rust In the second stage (outdoor 4-8 months), the weathering steel plate has less rust water, and the rust spots are small and dense; the ordinary steel plate has more rust water, and the rust spots are larger and thinner; the rust pillars and tear marks of the ordinary steel plate are more serious. There are signs of blackening at the bottom of the workpiece.
The third stage of steel plate rusting (more than 8 months outdoors), weather-resistant steel plate has a clear and dense rust core layer, and the rust points are tightly adhered to form a protective layer, and the rust is hardly rusted by hand rubbing; ordinary steel plate has a lot of rust , And even the whole piece of rust peeled off and the rust penetrated. Weathering steel plates are biased towards reddish brown, while ordinary steel plates are biased towards dark black.
