电磁搅拌对半固态钢铁组织的影响

研究电磁搅拌对半固态铸铁初生奥氏体和弹簧钢铸态组织的作用.研究表明:铸铁在凝固过程中,经过短时间的电磁搅拌,粗大的初生奥氏体枝晶就可以被破碎细化,而且随着搅拌功率的加大,初生奥氏体更加球状化或非枝晶化;经过电磁搅拌,引起铸铁熔体的强烈流动和温度起伏,加速了初生奥氏体枝晶二次臂的熔断和一次臂的缩短,最终使树枝状初生奥氏体转变为球状的初生奥氏体.研究还表明:电磁搅拌可以明显细化弹簧钢的柱状枝晶,代之以细等轴晶.

Effect of Electromagnetic Stirring on the Primary Austinite in the Semi-Solid Cast Iron and Spring Steel

The effects of electromagnetic stirring on the primary austenite in the cast iron and as-caststructures of the spring steel was studied.The experiments had shown that the primarily large austenitic dendrites can be fined when stirred by electromagnetic field for a short time and the higher the stirring power,the more sphercal or dedendritic the primary austenite,and that the fluid flow and temperature fluctuation of the melt may be induced by stirring,and accelerate the remelting of the second arm and decrease of the length of the first arm so that the primarily dendritic austenite is changed to spherical shape finally.That the column dendrites of the samples of spring steel can be also fined by the strong electromagnetic stirring and changed into fine equiaxed grains.