摘要
Pulsed magneto-oscillation （PMO） as a new electromagnetic technology to generate the grain refinement in metals and alloys was significantly developed in recent years. The influence of electromagnetic parameters on the grain size reduction in pure AI was investigated under the application of PMO with a constant inputting power. The experimental results show that the grain refinement degree could be improved with the increase in the current intensity in the case of the identical power. Moreover, through analysing the electromagnetic force and resistance force applied on the nucleus, a criterion of the nucleus detached from the mould wall was constructed. Based on the criterion, the detachment of nuclei with finer radius could cause better effect of the grain refinement, when applying a higher current peak. The movement of the detached grains was considered by analysing the influence of electromagnetic force and forced flow.
Pulsed magneto-oscillation （PMO） as a new electromagnetic technology to generate the grain refinement in metals and alloys was significantly developed in recent years. The influence of electromagnetic parameters on the grain size reduction in pure AI was investigated under the application of PMO with a constant inputting power. The experimental results show that the grain refinement degree could be improved with the increase in the current intensity in the case of the identical power. Moreover, through analysing the electromagnetic force and resistance force applied on the nucleus, a criterion of the nucleus detached from the mould wall was constructed. Based on the criterion, the detachment of nuclei with finer radius could cause better effect of the grain refinement, when applying a higher current peak. The movement of the detached grains was considered by analysing the influence of electromagnetic force and forced flow.
基金
Acknowledgements The authors acknowledge the financial support from the National Natural Science Foundation of China （Grant Nos. 51504048, 50574056 and U1760204） and the National Key Research Program of China （Grant No. 2017YFB0701800）.
