Ordinary carbon structural steel A572 grade 55 high strength steel has many impurities and low price. The ordinary carbon structural steel is used in places with low performance requirements and low strength, but it has good plasticity, toughness and cold deformation performance. High quality carbon structural steel has less harmful impurities, and its strength, plasticity and toughness are better than those of ordinary carbon structural steel. High quality carbon structural steel is mainly used to manufacture important mechanical parts.
A small amount of Nb is sufficient to obtain excellent comprehensive properties of A572 grade 55 high strength steel etc. steel material, because at low Nb concentration, the yield strength of steel material increases faster and is proportional to the concentration, but when the Nb content is greater than 0.03%, the strengthening effect begins to decrease. Studies have shown that when the Nb content is greater than 0.06%, excess Nb will no longer strengthen the steel material.
The difference between A572 grade 55 high strength steel, hot rolled sheet and cold rolled sheet: hot rolled sheet has low hardness, easy processing and good ductility. The cold-rolled sheet has high hardness and relatively difficult processing, but it is not easy to deform and has high strength. The cold rolled sheet is mostly used in automobile manufacturing and electrical products. Therefore, the two have their own characteristics. According to these characteristics, it is more appropriate to choose the right rolled plate to maximize its effect and benefit.