本钢铁道车辆用LZ50钢车轴坯的研制

Development of LZ50 Steel Billet for Railway Vehicle Axle at Benxi Iron and Steel

本钢采用铁水预处理、12 0t顶底复吹转炉冶炼、LF +RH TB二次精炼、4 8t钢锭 80 0轧机成坯工艺试生产了铁道车辆用LZ5 0钢 (% :0 4 7～ 0 5 5C ,0 17～ 0 4 0Si,0 6 0～ 0 90Mn) 2 30mm× 2 30mm车轴坯。LZ5 0钢材中氢含量为 (0 5～ 0 7)× 10 -6,氧 (9～ 10 )× 10 -6,氮 (5 5～ 70 )× 10 -6。A +C类非金属夹杂级别为1 0～ 2 5。LZ5 0钢 84 0℃正火处理后的机械性能为σs370～ 385MPa ,σb710～ 735MPa ,δ52 1%～ 2 3%。

The 230mm × 230mm billet of LZ50 steel (0.47～0.55C-0.17～0.40Si-0.60～0.9Mn) for railway vehicle axle has been developed at Benxi Iron and Steel by hot metal pretreatment, 120 t top and bottom combining blown converter melting, LF+RH-TB secondary refining, 4.8 t ingot 800 mill rolled billet process. The hydrogen content in finished LZ50 steel billet was (0.5～0.7)×10 -6, oxygen content (9～10)×10 -6, nitrogen content (55～70)×10 -6, and A+C inclusion rating units 1.0～2.5. The mechanical properties of LZ50 steel normalized at 840 ℃ were σ s 370～385 MPa, σ b 710～735 MPa, and δ 5 21%～23%.