采用新型微氮合金化技术对HRB400E带肋钢筋进行生产试制研究,发现其钢坯在750~850℃存在热塑脆性区,通过控制连铸工艺可获得优质钢坯;钢筋成品具有较高抗拉强度和合适屈强比,时效性能稳定,其金相组织均以铁素体+珠光体组成。研究表明,新型微氮钢筋的强度增加主要是由大小为5~30 nm的第二相粒子析出强化作用引起的,可以使钢筋的合金钒用量节约40%~60%。采用该工艺生产的螺纹钢每吨钢的成本降低了40~60元,产生了显著的经济效益。 The new micro-nitrogen alloying technology HRB400E ribbed steel production trial research found that the billets exist in the thermoplastic brittle zone at 750 ~ 850 ℃, by controlling the continuous casting process can be obtained high-quality billet; steel products with high tensile strength and The appropriate yield strength ratio, aging performance and stability, the microstructure are ferrite + pearlite composition. The results show that the increase of the strength of the new micro-nitrogen steel is mainly caused by the strengthening and precipitation strengthening of the second phase particles with the size of 5 ~ 30 nm, which can save 40% -60% of the alloyed vanadium content in the steel bar. The cost per ton of steel rebar produced by the process is reduced by 40-60 yuan, resulting in significant economic benefits.