SiC在球墨铸铁生产中的使用方法及效果

摘要

介绍了SiC在感应电炉熔炼和冲天炉熔炼中的使用方法及效果,电炉熔炼的2种方案6组试棒的生产结果显示:添加SiC后,球化率都由85％提高到95％;石墨球数由最低31个/mm2增加到最多315个/mm2;强度由最低497 MPa提高到最高539 MPa;伸长率由最低7.3％增加到19.3％;硬度降低10 HB左右.冲天炉熔炼的2种方案6组试棒的生产结果显示:添加SiC后,球化率都由87％提高到95％;石墨球数由最低81个/mm2增加到最多297个/mm2;强度由最高537MPa降低到最低476 MPa;伸长率由最低11.4％增加到21.7％;硬度降低15 HB左右.通过以上对比,可以看出:在熔炼中添加SiC,球墨铸铁铁液的形核能力增强,石墨球数显著增加,过冷度减小.此外,还发现冲天炉熔炼添加SiC后,铁素体体积分数增加,导致强度和硬度有所降低.%SiC using method and effect in the induction furnace melting and cupola melting was introduced.The results of 6 melting furnace bars in 2 plans show that:After adding SiC,ductile rate increased from 85％ to 95％,number of graphite nodules increased from the lowest 31 mm-2 to a maximum of 315 mm-2.The strength increased from the lowest 497 MPa to the highest 539 MPa.Elongation rate increased from the lowest of 7.3％ to 19.3％.The hardness reduced by about 10 HB.The results of 6 cupola furnaces bars in 2 plans showed that after adding SiC,ductile rate increase from 87％ to 95％,number of graphite nodules from the lowest 81 mm-2 to a maximum of 297 mm-2.The strength decreased from the highest 537 MPa to the lowest 476 MPa.Elongation rate increased from the lowest 11.4％ to 21.7％.The hardness reduced by about 15 HB.By the comparison above,it could be seen that:Adding SiC in nodular iron liquid iron increased nuclear capability and the number of graphite nodules significant increased.Supercooling degree decreased.In addition,it was found ferrite volume fraction increased after adding SiC,resulting in decreased strength and hardness.