汽车横梁用新型含钒合金钢的铸造性能和显微组织研究

Study on Castability and Microstructure of New Vanadium-bearing Alloy Steel for Automobile Crossbeam

摘要: 研究了不同钒含量的22MnB5Vx (x=0,0.25,0.5,0.75)汽车横梁用新型含钒合金钢的铸造性能和显微组织。结果表明：钒含量对钢的铸造性能和显微组织有明显影响，随钒含量从0逐步增大到0.75wt%时，试验钢的显微组织先细化后粗化，流动性和抗热裂性先增强后减弱，铸造性能先提高后下降。与未添加钒的钢相比，钒含量为0.5%的钢液流程长度由511 mm增大到630 mm，裂纹长度由3.5 mm减小为0。当钒含量为0.5%时，含钒合金钢可获得细小的内部组织和良好的铸造性能。

Abstract: The castability and microstructure of 22MnB5Vx（x =0, 0.25, 0.5, 0.75） alloy steel with different vanadium contents for automobile crossbeam were studied. The results show that the vanadium content has an obvious effect on the castability and microstructure of the steel. With the increase of vanadium content from 0% to 0.75wt%, the microstructure of the steel is refined first and then coarsened, the fluidity and hot cracking resistance are enhanced first and then weakened, and the castability is improved first and then decreased. Compared with those of the steel without vanadium, the flow length of molten steel with vanadium content of 0.5% increases from 511mm to 630 mm, and the crack length decreases from 3.5 mm to 0. When the vanadium content is 0.5%, the vanadium alloy steel can obtain fine internal structure and good casting performance.