摘要
This article discusses the effect of temperature field on the Pulse Magneto-Oscillation(PMO) induced solidification refinement of pure aluminium to provide more information for the industrial application of the PMO solidification technology.The temperature field is altered mainly by applied variable cooling conditions and pulse parameters.Experimental results show that the refinement effect in the case of full sand mould applied is weakened with the decreasing of cooling rate,however,in the alternative case,the sand mould whose sand bottom was replaced by a graphite block is favorable to the survival of equiaxed nucleus.The refinement mechanism is discussed in terms of the relationship between temperature field and the formation process of solidified structure.The formation or survival of nucleus depends on both temperature field and Joule heat produced by PMO,both low pulse frequency and high pulse current were experimentally confirmed to be effective;and PMO was demonstrated high potential in industrial application.
This article discusses the effect of temperature field on the Pulse Magneto-Oscillation (PMO) induced solidification refinement of pure aluminium to provide more information for the industrial application of the PMO solidification technology. The temperature field is altered mainly by applied variable cooling conditions and pulse parameters. Experimental results show that the refinement effect in the case of full sand mould applied is weakened with the decreasing of cooling rate, however, in the alternative case, the sand mould whose sand bottom was replaced by a graphite block is favorable to the survival of equiaxed nucleus. The refinement mechanism is discussed in terms of the relationship between temperature field and the formation process of solidified structure. The formation or survival of nucleus depends on both temperature field and Joule heat produced by PMO, both low pulse frequency and high pulse current were experimentally confirmed to be effective; and PMO was demonstrated high potential in industrial application.
基金
supported by the National Natural Science Foundation of China (No.50734008 and No.50574056)