中文摘要：

探讨了钒含量对高氮20MnSi螺纹钢组织和室温冲击韧性的影响，并利用扫描电镜对试验钢的宏观和微观断口形貌进行分析。结果表明：随钒含量的增加，高氮20MnSi螺纹钢晶粒由8．6μm变化到2．1μm，显著细化了晶粒；常温下钒提高了试验钢冲击韧性的敏感程度，钒含量的增加使冲击功由5．8J变化到97．2J，并且当钒含量为0．047％时，冲击功达到99．6J；在高氮条件下，钒含量的增加使20MnSi螺纹钢脆性区转变为塑性区，但在C含量高（0．052％）的试验钢中冲击韧性有所降低。

英文摘要：

The effects of vanadium content on the microstructure and impact toughness at room temperature of high nitrogen 20MnSi rebar groups were discussed. By using scanning electron microscopy （SEM）, the macroscopic and microcosmic fracture morphology of the steel was analyzed. The results show that with the increase of vanadium content, high content of nitrogen 20MnSi rebar grain changes from 8.6 μm to 2.1 μm, and the grain size is significantly refined. At room temperature, vanadium improves the sensitivity of test steel impact toughness, and the increase in vanadium content makes impact energy change from 5.8 J to 97.2 J, and when the content of vanadium is 0.047%, and the impact energy is 99.6J. Under the content of high nitrogen, the increase in vanadium makes brittle zone of 20MnSi rebar change into a plastic zone, but the impact toughness of test steel with high content of C（0.052%） decreases.