本发明涉及一种高强度低碳贝氏体耐火钢及其制备方法，属于低碳空冷贝氏体耐火钢技术领域，解决了现有技术中耐火钢的屈服强度低，生产工艺繁杂和高温力学性能差的问题。一种高强度低碳贝氏体耐火钢，其化学组成按质量百分比计为：C：0 .07％‑0 .1％、Si：0 .7％‑0 .9％、Mn：1 .0％‑1 .5％、Cr：0 .7％‑0 .8％、Ni：1 .0％‑1 .3％、Cu：0 .3％‑0 .35％、Mo：0 .6％‑0 .8％、Nb：0 .0 25％‑0 .0 3 5％、V：0 .0 9％‑0 .1 5％、Ti：0 .01％‑0 .015％、(Nb+V+Ti) <0 .2％、Alt＜ 0 .02％、S＜0 .003％、P＜0 .008％，余量为铁和不可避免的杂质。本发明提高了耐火钢的屈服强度和高温力学性能。

The invention relates to a high strength low carbon bainite refractory steel and a preparation method thereof, belonging to the technical field of low carbon air cooling bainite refractory steel, and solves the problems of low yield strength, complicated production process and poor high temperature mechanical properties of refractory steel in existing technologies. A kind of high-strength low-carbon bainite refractory steel, whose chemical composition is as follows : C : 0.07 % – 0.1 %, Si : 0.7 % – 0.9 %, Mn : 1.0 % – 1.5 %, Cr : 0.7 % – 0.8 %, Ni : 1.0 % – 1.3 %, Cu : 0.3 % – 0.35 %, Mo : 0.6 % – 0.8 %, Nb : 0.025 % – 0.035 %, V : 0.09 % – 0.15 %, Ti : 0.01 % – 0.015 %, ( Nb + V + Ti ) < 0.2 %, Alt < 0.02 %, S < 0.03 %, P < 0.018 %, and the rest is iron and inevitable impurities. The invention improves the yield strength and high temperature mechanical properties of refractory steel.