Identify true and false EN10025-5 S235J2W weathering steel plate

To distinguish the authenticity of EN10025-5 S235J2W weathering steel plate, we must first understand the rusting process of weathering steel and ordinary steel. The following can clearly reflect the difference between ordinary steel plate and EN10025-5 S235J2W weathering steel plate.

EN10025-5 S235J2W weathering steel plate: small rust spots begin to appear in the initial stage. There is less rust water in the middle stage, and the rust spots are small and thick.

In the stable period, a clear and dense rust core layer is formed, and the rust spots are closely adhered to form a protective layer. The rust is hardly peeled off by hand rubbing, and it tends to be dark black. (7-8 years for normal environment, about 2 years for coastal environment)

Ordinary steel: The initial rust spots are relatively loose. In the middle stage, there is more rust water, the rust spots are larger and thinner; the rust pillars and tear marks are more serious. There are signs of blackening at the bottom of the workpiece.

During the stable period, there is a lot of rust loss, even the whole piece of rust peels off, the rust wears out, and tends to be reddish brown or yellowish brown.

It can be seen that the rust appearance of ordinary steel and EN10025-5 S235J2W weathering steel plate is not obvious within 6 months after rusting. The reason is that 6 months ago, the dense protective rust layer of EN10025-5 S235J2W weathering steel plate still There is no real growth, so it is difficult to distinguish the true and false of EN10025-5 S235J2W weathering steel plate with the naked eye in the early stage.