摘要
以某钢厂GCr15钢大方坯为研究对象,采用ProCAST软件建立凝固数学模型,在此基础上采用CAFE模型对铸坯凝固组织进行模拟,研究了过热度、拉速和二冷强度对铸坯凝固组织的影响。结果表明:过热度对铸坯凝固组织影响较大。随着过热度的提高,同一位置柱状晶区平均晶粒半径增大,柱状晶区增大,中心等轴晶比例减小,柱状晶向等轴晶转变延后,过热度由40℃降低至10℃时,中心等轴晶率增加21.14%。拉速和二冷强度对铸坯凝固组织影响较小。随着拉速的提高或二冷强度的降低,柱状晶区减小,中心等轴晶比例增大,柱状晶向等轴晶转变提前,但其变化并不明显。在实际生产过程中可以通过降低过热度来细化铸坯凝固组织晶粒。
The solidification mathematical model was established by ProCAST software on a GCr15 steel bloom and then the CAFE model was used to simulate the solidification structure of the bloom. The effects of superheat , casting speed and secondary cooling intensity on the solidification structure of bloom were studied. The results showed that superheat had great influence on solidification structure of bloom. With the increase of superheat degree, the average grain radius increased at the same position of the columnar zone, the columnar region increased, the equiaxial crystal ratio decreased and the CET transition was de- layed. When the superheat degree decreased from 40 ~C to 10 ~C ,the equiaxial crystal ratio increased by 21.14%. The casting speed and the secondary cooling intensity had little influence on the solidification structure of the bloom. With the increase of the casting speed or the decrease of the secondary cooling in- tensity, the columnar region decreased, the equiaxial crystal ratio increased, and the CET transition ahead of time, but the changes were not obvious. In the actual production process, the grain size of the solidifica- tion structure of the billet can be refined by reducing superheat.
出处
《钢铁钒钛》
CAS
北大核心
2017年第6期121-127,共7页
Iron Steel Vanadium Titanium
基金
国家高技术研究发展计划(863计划)资助项目(2015AA03A502)
