摘要
为了解脉冲磁致振荡(pulse magneto-oscillation,PMO)技术对GCr15轴承钢定向凝固组织的作用,通过改变PMO参数和抽拉速率,研究了不同抽拉速率下PMO对定向凝固GCr15轴承钢枝晶臂间距的影响。结果表明:在相同抽拉速率下,PMO的峰值电流依次为150、250、350ki A时,GCr15轴承钢的一次和二次枝晶臂间距先增大后减小。当峰值电流固定为350ki A时,随着PMO频率从90、240、390kf Hz依次增大,一次枝晶臂间距先减小后增大,二次枝晶臂间距逐渐变大。同时,随着抽拉速率的提高,枝晶臂间距减小幅度逐渐降低。通过测量温度梯度发现,在PMO作用下,固-液界面前沿液相中温度梯度的提高和溶质分布的变化,是枝晶臂间距减小的主要原因。
In order to understand the effect of pulsed magnetooscillation(PMO)technique on the directionally solidified structure of GCr15 bearing steel,the influence of PMO on the dendrite arm spacing of directionally solidified GCr15 bearing steel under different pulling rates conditions was investigated by changing PMO parameters and pulling rates.The results showed that the primary and secondary dendrite arm spacings of GCr15 bearing steel increased at first and then decreased when the peak current of PMO was 150,250 and 350 ki A under the same pulling rate condition.When the peak current was fixed at 350ki A,with the increase in PMO frequency from 90,240,390kf Hz in turn,the primary dendrite arm spacing decreased at first and then increased,and the secondary dendrite arm spacing gradually increased.At the same time,the amplitude of dendrite arm spacing decreasing decreased gradually with the increase in pulling rate.The temperature gradient measurement showed that the increase in temperature gradient and the change of solute distribution in the liquid phase at the front of the solidliquid interface were the main reasons for the decrease in dendrite arm spacing under the action of PMO.
作者
李涛
李莉娟
李开创
邹富康
罗坤坤
翟启杰
LI Tao;LI Lijuan;LI Kaichuang;ZOU Fukang;LUO Kunkun;ZHAI Qijie(Center for Advanced Solidification Technology,Shanghai University,Shanghai 200444,China)
出处
《上海金属》
CAS
2023年第5期62-69,74,共9页
Shanghai Metals
基金
国家重点研发计划(2020YFB2008400)
国家自然科学基金(52130109)。
