Casting Process of High Quality ASTM A588 Grade A Weathering Steel

ASTM A588 Grade A weathering steel, also known as atmospheric corrosion resistant steel, is adopted in ordinary steel. A low-alloy steel made by adding a certain amount of alloying elements, the main alloying components are Cu, P, Cr, Ni and other elements. The atmospheric corrosion resistance of weathering steel is 2 to 8 times that of ordinary carbon steel. ASTM A588 Grade A weathering steel has good mechanical and welding properties, and the longer the use time, the more obvious the corrosion resistance effect.

Due to the corrosion resistance of ASTM A588 Grade A weathering steel compared with ordinary carbon steel and the economy compared to stainless steel, ASTM A588 Grade A weathering steel has developed rapidly, mainly used in transportation, power transmission, transportation, construction and other fields. Grade A weathering steel contains Cu, the billet shell has a certain affinity with the copper plate of the mold, and the billet shell is easily adhered to the copper plate, resulting in bond breakout. The carbon content of this steel is 0.10%~0.15%, which belongs to the range of peritectic steel, and peritectic reaction occurs in the solidification process of peritectic steel.

In the process of continuous casting, the inscription layer on the surface of the mold is seriously worn, the copper tube of the mold is bonded with the high-temperature casting billet, the copper plate is partially melted, and the Cu in the liquid phase penetrates into the iron matrix through the austenite grain boundary, and the Cu is in the iron matrix. The enrichment of austenite grain boundaries will reduce the plasticity of ASTM A588 Grade A weathering steel, and it is easy to produce slab cracks when the pulling speed is too fast.

The chemical composition of ASTM A588 Grade A weathering steel meets the standard requirements, the composition of C, Si, Mn, Cr, Ni, Cu, Nb is controlled stably, the harmful elements of P and S are controlled within a low range, and Ni/Cu>0.5 effectively prevents the Cracks occur in the slab to ensure the quality of ASTM A588 Grade A weathering steel. According to the relevant data, due to the low control range of C content, the impact of the steel strip at 0°C is higher than the standard requirements, the yield strength and tensile strength margins are reasonable, and the elongation meets the standard requirements.