合金元素对34Mn2V钢凝固组织的影响

Influence of Alloying Elements on Solidification Structure of 34Mn2V Steel

为改善34Mn2V钢大圆坯断面凝固组织结构,采用CAFE′法对断面凝固组织进行了模拟计算,研究了钢液中主要合金元素含量对凝固组织的影响规律。模拟结果表明:在钢种成分允许范围内,适当提高Si含量有助于增加晶粒数目和中心等轴晶率、减小晶粒平均半径,当Si含量超过一定限度后,三者将保持平稳不再大幅变化;Mn含量的提高也可增加形核数目和中心等轴晶率,但增幅相对较小;V含量的调整几乎不能引起凝固组织结构的变化。对34Mn2V钢主要合金元素含量进行优化调整后,模拟结果显示,铸坯凝固组织中的晶粒数目较优化前增加了27.71%,晶粒平均半径减小了18.75%,中心等轴晶率增加了43.24%,凝固组织结构较为理想。

In order to improve the solidification structutre of 34Mn2V round bloom in cross section, the microstructure was obtained by a CAFE approach. And the influence rule of the amount of main alloying elements on solidification structure was carded on research. The simulated results show that, in the allowable range of the steel composition, appropriate increasing Si content is helpful to increase the number of grains and the equiaxial crystal rate in center, reduce the average grain radius, but once the Si content exceed a certain limit, the three would remain stable. Increasing Mn content also has the same effect. The adjustment of V content can not cause any changes of solidification structure nearly. After optimizing and adjusting the content of main alloying elements, the simulated results show that the number of grains is increased by 27.71%, the average grain radius is decreased by 18.75%, and the equiaxial crystal rate in the center is increased by 43.24%. The obtained solidification structure is more ideal.