【摘要】 采用50 kg真空感应电炉冶炼质量分数为4%Cr、0.8%C及少量N、Re的8Cr4MoV低合金冷轧工作辊试验钢,经过锻造、预备热处理试验后,检验试验钢的力学性能、微观组织,选择综合性能较好的钢种开展最终热处理试验,确定淬火工艺,然后利用选定的钢种和工艺试制武钢冷轧厂冷连轧机φ610 mm×1 700 mm超深淬硬层冷轧工作辊。试制工作辊毛坯采用电炉+真空脱气+电渣重熔工艺冶炼,夹杂物和有害气体含量低,辊身采用50/250 Hz双频感应加热淬火,虽然未采用深冷处理,其金相组织、硬度和超声波探伤结果较好,尤其残余奥氏体含量较低,符合试制工作辊技术要求。试用效果表明其耐磨性较高,使用寿命达到Cr2常规工作辊的1.6倍,淬硬层深度与Cr5超深淬硬层冷轧工作辊相当,且没有发生剥落,具有较好的抗事故性。更多还原

【Abstract】 8Cr4MoV low alloyed cold work roll steels were smelted by 50 kg vacuum induction furnace,containing about 4%Cr,0.8%C,and appending a little of N and Re in it individually or together.After forged,quenched and tempered,the steels′ mechanical properties and microstructures were examined and compared each other.The better was put into final heat-treatment test to determine the quenching temperature,and then to trial-manufacturing super-deep hardening layer cold work rolls of 1 700 mm body length for 4 H tandem cold mill in Cold Strip Mills WISCO.Through the process of EAR+LF+VD+ESR,the trial steels were made with low content of inclusions and harmful gases.The body was quenched by 50/250 Hz induction hardening equipment without liquid nitrogen treatment.The trial-roll microstructure,hardness and ultrasonic inspection were very good,especially the amount of residual austenite under control.The trial-roll performances show that their wear-resistance is higher,service life is longer about 1.6times of Cr2 conventional cold work roll,the hardening layer depth is deeper corresponding to Cr5 super-deep hardening layer cold work roll,and no spalling,accident-resistance is better.更多还原