大功率电力机车车轴用EAlN钢的生产工艺实践

Process Practice of Steel EAIN for Axle of High Power Electric Locomotive

车轴用钢EAlN(/%:0.32~0.38C,0.15~0.35Si,0.80~1.10Mn,≤0.015P,≤0.010S)300 mm×300mm钢坯试制流程为60 t电弧炉-LF-VD-8.4 t铸锭-1 000 mm初轧机开坯工艺。通过EAF热装≥70%的预处理铁水,EAF控制终点[P]≤0.008%和[C]≥0.10%,出钢留钢10%,高碱度渣(CaO)/(SiO_2)=4~7并喂Al线精炼,控制[Al]s 0.020%~0.040%,VD后喂0.5 kg/t Si-Ca线,氩气保护浇铸等工艺措施,使生产的EAlN钢的洁净度为[O]≤15×10^(-6),[H]≤1.0×10^(-6),[N]≤80×10^(-6),P≤0.015%,S≤0.005%,A、B、C、D类非金属夹杂物级别≤1.0,EAlN车轴钢坯和车轴技术指标符合大功率电力机车车轴的技术要求。

The pilot production flow sheet for 300 mmx 300 mm bloom of steel EA1N （/% ： O. 32 -0. 38C, 0. 15 0. 35Si, 0. 80 - 1.10Mn, ≤0. 015P, ≤0. 010S） for axle is 60 t EAF-LF-VD-8.4 t ingot casting-1 000 mm blooming mill breakdown process. With the process measures including EAF hot charging ≥70% pre-treating hot metal, EAF controlling end [ P] ≤0. 008P and [ C] ≥0. 10%, 10% heel liquid in tapping, refining with high basicity slag （ CaO）/（ SiO2 ） =4 N 7 and feeding A1 wire to control [A1]s 0. 020% NO. 040% , after VD process feeding 0. 5 kg/t Si-Ca wire and argon shiel- ding ingot casting, the cleanliness of produced steel EA1N is [ O] ≤15 ×10-6, [ H] ≤ 1.0 ×10-6, [ N] ≤80 ×10-6, p≤ 0. 015%, S≤0. 005% , and inclusion rating of A, B, C and D series ≤1.0; the technical indexes of bloom and axle of steel EA1N all meet specification requirement for axle of high power electric locomotive.