摘要
利用移动边界法得到22CrMoH连铸坯凝固过程中的温度场,在此基础上采用元胞自动机--有限元(CAFE)法对22CrMoH齿轮钢连铸坯的微观组织进行数值模拟,模拟结果与实际样品微观组织形貌基本吻合;探讨了Cr、Mo、Si和Mn等合金元素含量对铸坯微观组织的影响趋势.结果表明,在该钢号规定的范围内,适当提高Si、Mn元素含量能够提高等轴晶比例,使晶粒数目增加,晶粒平均半径减小;Mo含量的提高能够明显增加形核数量;适当减少Cr含量有助于提高等轴晶的比例,但对晶粒数目和尺寸影响较小.对22CrMoH钢中合金元素进行优化调整结果显示,连铸坯凝固组织得到了明显改善,等轴晶的比例提高近1倍,晶粒数目提高了19.96%,晶粒平均半径减小9.20%.
The temperature filed of 22CrMoH billets in continuous casting was simulated by using a moving boundary method. Based on a CAFE （cellular automaton-finite element analysis） approach, the microstructure of 22CrMoH billets was obtained and it agrees reasonably well with experimental data. The effects of alloying elements such as Cr, Mo, Si and Mn on the microstructure of 22CrMoH billets were studied. The results suggested that within the specified scope of the 22CrMoH grade, with the contents of Si and Mn increasing, the proportion of equiaxed grains increased, and the number of grains raised, hence the average radius reduced. The increased content of Mo tends to enhance the formation of nuclei, and a proper decrease of Cr element is conducive to raise the ratio of equiaxed grains while has little influence on the number and average radius of grains. Finally, the contents of Cr, Mo, Si and Mn in 22CrMoH steel was optimized, and the simulated results show that the microstructure of 22CrMoH billets is greatly improved： the proportion of equiaxed grains becomes near double, the number of grains increases by 19.96% , and the average grain radius decreases by 9.20%.
出处
《北京科技大学学报》
EI
CAS
CSCD
北大核心
2011年第9期1091-1098,共8页
Journal of University of Science and Technology Beijing
基金
中国博士后基金资助项目(20100470005)
关键词
齿轮钢
合金元素
连铸坯
微观组织
数值方法
计算机模拟
gear steels
alloying elements
billets
microstructure
numerical methods
computer simulation
