本发明公开了一种MC析出增强型高强耐火耐蚀钢及其制造方法，属于建筑结构用钢技术领域，采用低C设计，采用Ni耐蚀元素合金化，并进行Mo-Nb-V复合微合金化，耐火性主要通过室温贝氏体组织控制和遇火高温析出纳米MC粒子共同保障。其组成为：C：0 .01～0 .04wt .％、Si：0 .10～0 .30wt .％、Mn：0 .10～0 .50wt .％、Ni：3 .00～5 .00wt％、Cu：0 .20～0 .40wt .％、Mo：0 .15～0 .20wt .％、Nb：0 .01～0 .10wt .％、V：0 .01～0 .08wt .％、Ti：0 .010～0 .030wt .％、Al：0 .015～0 .035wt .％、P：<0 .015wt .％、S：<0 .010wt .％，其余为Fe和不可避免的杂质。制造方法采用转炉或电炉冶炼，铸造采用连铸或模铸。上述MC析出增强型高强耐火耐蚀钢可用于钢结构建筑。

The invention discloses a MC precipitation-enhanced high-strength fire-resistant and corrosion-resistant steel and its manufacturing method, which belongs to the technical field of steel for building structures. It adopts low-C design, adopts Ni corrosion-resistant element alloying, and carries out Mo-Nb-V composite microalloying. The fire resistance is mainly guaranteed by the control of room temperature bainite structure and the precipitation of nano-MC particles at high temperature after fire. The compositions are : C : 0.01 ~ 0.04wt. %, Si : 0.10 ~ 0.30wt. %, Mn : 0.10 ~ 0.50wt. %, Ni : 3.0 ~ 5.0wt. %, Cu : 0.20 ~ 0.40wt. %, Mo : 0.15 ~ 0.20wt. %, Nb : 0.01 ~ 0.10wt. %, V : 0.01 ~ 0.08wt. %, Ti : 0.01 ~ 0.030wt. %, Al : 0.015 ~ 0.035wt. %, P : < 0.015wt. %, S : < 0.010wt. %, the others are Fe and inevitable impurities. The manufacturing method is converter or electric furnace smelting, casting is continuous casting or mold casting. The above MC precipitation-enhanced high strength fire and corrosion resistant steel can be used for steel structure buildings.