摘要
为了探讨移动电磁场对低碳钢凝固过程枝晶破碎的影响,进行了移动电磁场下的0.22%～0.34%C(质量分数)低碳钢浇铸凝固实验.对不同磁感应强度下铸坯凝固组织进行了观察,考察了二次枝晶分布,凝固过程冷却速度与二次枝晶间距的函数关系.同时考察了移动电磁场对铸坯柱状晶向等轴晶转变(CET)位置的影响,并对钢凝固过程CET发生时的凝固速度和固相率进行了计算.导出了移动电磁场下合金凝固过程枝晶破碎的临界条件,并通过低碳钢作实验验证,得到了低碳钢凝固CET发生时临界固相率和液相平均流速之间的关系.
To investigate the effect of travelling electromagnetic field on dendrite fragmentation in solidification process,the 0.22wt%～0.34 wt%C steel was tested for its solidifying behavior in travelling electromagnetic field.Observing the solidification structures of casting blanks under different magnetic flux density,the distributions of secondary dendrite arm spacing were investigated and the functional relationship between secondary dendrite arm spacing and cooling rate in solidification was discussed,as well as the effect of travelling electromagnetic field on the columnar-to-equiaxed transition（CET）position.The solidification rate and solid fraction when CET occurs were calculated.The critical conditions for dendrite fragmentation in travelling electromagnetic field is derived and verified by the testing results of low carbon steel.Thus,the relationship between the average velocity of the liquid-phase and the critical solid volume fraction when CET occurs was obtained.
出处
《东北大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2010年第12期1717-1720,1732,共5页
Journal of Northeastern University(Natural Science)
基金
高等学校学科创新引智计划项目(B07015)
国家自然科学基金资助项目(50674021)
关键词
二次枝晶间距
枝晶破碎
柱状晶向等轴晶转变
固相率
secondary dendrite arm spacing
dendrite fragmentation
CET（columnar-to-equiaxed transition）
solid fraction
