脉冲电场孕育处理对伍德合金凝固组织的影响

Effect of Electric Pulse Modification on Solidification Structure of Wood Alloy

以伍德合金为研究对象,在熔融状态下对其进行脉冲电场孕育处理,分析脉冲电压、孕育处理时间、脉冲频率对伍德合金凝固组织的影响。结果表明,脉冲电场孕育处理可以细化伍德合金的凝固组织,使其中的Cd相平均尺寸变小。一定电压范围内,随着脉冲电压的增大,伍德合金凝固组织细化程度愈明显,电压增大到6 V后,细化作用减弱;孕育处理效果与处理时间密切相关,一定时间范围内,随处理时间的延长,伍德合金凝固组织细化程度愈明显,40 s时Cd相平均尺寸最小,为29.86μm,较未处理时减小了63.60%,之后细化程度减弱;随着脉冲频率的增大,脉冲孕育处理细化伍德合金凝固组织的效果先增强后减弱,脉冲频率为50 Hz时,细化效果最明显,凝固组织中Cd相平均尺寸为24.15μm。

Taking molten Wood alloy as the research object, pulsed electric field madipication was carried out. The effect of pulse voltage, treatment time and pulse frequency on the solidification structure of Wood alloy during solidification was investigated. Experimental results show that the solidification structure of Wood alloy can be refined by electric pulse modification, and the average size of Cd phase becomes smaller. In the given range pulse voltage, with pulse voltage increasing, microstructure refining effect gets better, when the voltage is bigger than6 V, the function of refining grains weakens; Modification effect is closely related to treatment time, in a certain time range, longer time leads to better refining effect when treatment time is 40 s, the minimum average size of Cd phase is 29.86 μm, by contrast, the size decreases to 63.60% of the untreated sample. With increasing the pulse frequency, refining effect first increases, and then decreases, when the pulse frequency is 50 Hz, the best effect is obtained, the average size of Cd phase in the solidification structure is 24.15 μm.