电脉冲对高硼中碳合金钢凝固组织的影响

Effects of Electric Pulse on Solidification Structure of High-Boron Middle-Carbon Alloy Steel

研究了高硼中碳合金钢凝固过程中施加电脉冲的凝固组织。结果表明,经过电脉冲处理,高硼中碳合金钢晶粒得到细化,晶粒形状趋于圆整,分布更加均匀,马氏体片层间距减小,硬质相体积分数由未经电脉冲处理时的10.6%降低到8.3%,基体中W、Cr、Mo、V等合金元素含量上升,基体硬度由HV664提高到HV730,网状硬质相产生断网现象,并且有孤立球化趋势。分析认为,以上是电脉冲的焦耳热效应、电磁力作用、电迁移效应共同作用的结果。

Effect of electric pulse on the solidification structure of high-boron middle-carbon alloy steel was investigated by exerting electric pulse on the alloy steel during solidification process. The results in- dicate that, after electric current pulse treatment, grains of high-boron middle-carbon alloy steel are re- fined and spheroidized with more uniform distribution. Martensite lamellar spacing is decreased, and volume fraction of hard phase is decreased from 10.6 % in non-electric pulse treatment to 8.3 %, howev- er, alloying elements, such as W, Cr, Mo, V in matrix are increased. In addition, hardness of matrix is improved from HV664 to HV739. Net-like hard phase exhibits discontinuous and isolated spheroidiza- tion. The co-action of Joule heat, magnetic-electric force and electric migration of electric pulse is re- st^onsihle for the above effects.