本发明公开了一种功能复合化高强度建筑结构用钢及其制造方法，属于建筑结构用钢技术领域，采用低C设计，采用Cu、Ni、Cu多元适量合金化，并进行Nb微合金化，耐候性主要由Cu、Ni、Cr 等耐蚀元素耦合保障，耐火性则由Cr、Cu、Nb等元素提高组织热稳定性和遇火析出增强来保障。其组成为 ：C ：0 .0 1～ 0 .0 4 w t .％ 、S i ：0 .1 0～ 0 .30wt .％、Mn：0 .10～0 .50wt .％、Cu：0 .80～ 1 .50wt .％、Ni：0 .40～0 .80wt％、Cr：0 .40～ 0 .80wt％、Nb：0 .01～0 .05wt .％、Ti：0 .010～ 0 .0 3 0w t .％、Al：0 .01 5～0 .0 3 5w t .％、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。上述功能复合化高强度建筑结构用钢可用于钢结构建筑。

The invention discloses a functional composite high-strength building structure steel and a manufacturing method thereof, which belongs to the technical field of building structure steel, adopts low C design, adopts Cu, Ni, Cu multiple appropriate amount alloying, and Nb microalloying. Weather resistance is mainly guaranteed by coupling of corrosion resistant elements such as Cu, Ni, Cr, etc. Cr, Cu, Nb and other elements enhance the thermal stability of the microstructure and enhance the precipitation during fire. The composition is as follows: C: 0 01 ~ 0 04 wt. %, S: 0 10 ~ 0 30 wt. %, Mn: 0 10 ~ 0 50 wt. %, Cu: 0 80 ~ 1 50 wt. %, Ni: 0 40 ~ 0 80 wt. %, Cr: 0.40 ~ 0.80wt %, Nb: 0.01 ~ 0.05wt %, Ti: 0. <0.010 wt. %, the rest is Fe and inevitable impurities. The manufacturing method uses converter or electric furnace smelting, casting using continuous casting or die casting. The steel used in the functional complex high strength building structure can be used in steel structure building.