合金元素对20CrMnTi凝固组织影响的数值模拟

利用CA（元胞自动机）和FE（有限元）耦合模型,模拟齿轮钢中Si、 Mn、 Cr、 Ti 4种元素对连铸坯凝固组织的影响。模拟所得温度场和凝固组织跟实际数据基本吻合。在国标规定的成分范围内, Si含量增加可降低钢种液相线温度,增加形核动力,从而增加晶粒数目,细化晶粒; Ti含量可增加钢中异相形核数,从而增加晶粒数目,细化晶粒; Si, Ti含量增加还可降低枝晶尖端生长速度,从而减小柱状晶区域,扩大等轴晶区域; Mn, Cr含量变化对于钢种的液相线温度以及枝晶尖端生长速度影响不大,因此对于晶粒数目,等轴晶面积影响较小。

The Numerical Simulation of Effects of Alloying Elements on 20CrMnTi Solidified Structure

The effects of alloying elements such as Si, Mn, Cr, Ti on billet solidified structure were simulated by using CA （cellular automation） and FE（finite element） coupling model. Temperature field and solidified structure got by simulation agree reasonably well with experimental data. In the composition range of the national standard, the growth of Si content can reduce the liquidus temperature, increase nucleation power, thereby increasing the number of grains and refining grains. The growth of Ti content can increase heterogeneous nucleation number, thereby increasing the number of grains and refining grains; The growth of Si, Ti content can also reduce the growth rate of dendrite tip, thereby reducing the area of columnar crystals and expanding equiaxed crystal area. The growth of Mn, Cr content has little effect on liquidus temperature and the growth rate of dendrite tip, So for the number of grains, equiaxed crystal area .