Microstructure of ASTM CortenA Steel

According to the coiling characteristics of ASTM CortenA steel, the tail and middle part of ASTM CortenA steel were sampled for metallographic analysis. After grinding and polishing, the sample was corroded with 4% nitric acid alcohol, and its metallographic structure was observed under an optical microscope. Due to the addition of Nb element for microalloying, the grain size of ASTM CortenA steel was higher.

The metallographic structure is basically ferrite and a small amount of pearlite. The tail of ASTM CortenA steel has a grain size of grade 9-10 due to the faster cooling rate after winding, and the middle part of ASTM CortenA steel has a slower cooling rate after winding. The grain size of the temperature phenomenon is 8-9.

Using BBN50t electric furnace-620mm narrow-band production line to produce ASTM CortenA steel, the chemical composition, casting quality and mechanical properties fully meet the requirements of American Standard ASTM and users. It has passed professional certification and has the ability to mass produce ASTM CortenA steel.