Abstract: A three-dimensional mathematical model for consumable-electrode vacuum melting process of 14Cr-13Co- 5Mo-2Ni gear steei (/% ： 0.014C, 0.26Si, 0.17Mn, 13.79Cr, 12.69Co, 4.66Mo, 2.00Ni, 0.53Al) diameter 290 mm, 9 t ingot has been established to study the effect of cooling water pressure, electric current and smelting rate on distribution of solidified structure and grain size of consumable-electrode vacuum melting ingot. Research results show that as the cooling water pressure increases from 6000 MPa to 8000 MPa, the current and smelting rate respectively decrease from 6.2500 kA and 1.250 kg/s to 6.228 6 kA and 1.125 kg/s, the equiaxed zone in melted ingot increases nearly by one fold, amount of grain increases by 45.17% , average grain size decreases by 17% and max spacing between secondary dendritic arms decreases by 4.88% , basically to achieve the object of grain fining and uniform distribution of alloying elements in steel.

Key words: 14Cr-13Co-5Mo-2Ni Gear Steel, Consumable-Electrode Vacuum Melting, Process Parameters, Numerical Simulation

摘要： 建立了14Cr-13Co-5Mo-2Ni齿轮钢(/%:0.014C,0.26Si,0.17Mn,13.79Cr,12.69Co,4.66Mo,2.00Ni,0.53Al)直径290 mm 9 t锭真空自耗熔炼过程三维数学模型,研究冷却水压、电流和熔化速率对自耗锭凝固组织分布及晶粒大小的影响。研究结果表明,当冷却水压由6000 MPa增加到8000 MPa,电流由6.2500 kA减小至6.2286kA,熔化速率由1.250 kg/s降低至1.125 kg/s后,冶炼的自耗锭内部等轴晶区域增大将近1倍,晶粒数目提高了45.17%,晶粒平均半径减小了17%,最大二次枝晶间距减小了4.88%,基本达到晶粒细化,合金元素分布均匀化的目的。

关键词: 14Cr-13Co-5Mo-2Ni齿轮钢, 真空自耗, 工艺参数, 数值模拟