Separation of primary Si phase and removal of boron in the primary Si phase during the solidification process of the Al-30%Si-10%Sn melt under a traveling magnetic field(TMF) were investigated. The results showed that...Separation of primary Si phase and removal of boron in the primary Si phase during the solidification process of the Al-30%Si-10%Sn melt under a traveling magnetic field(TMF) were investigated. The results showed that the agglomeration layer of the primary Si can be formed in the periphery of the ingot while the inner microstructures mainly consist of the eutectic α-Al+Si and β-Sn phases. The intense melt flow carries the bulk liquid with higher Si content to promote the growth of the primary Si phase which is first precipitated close to the inner wall of crucible with a relatively lower temperature, resulting in the remarkable segregation of the primary Si phase. The content of impurity B in the primary Si phase can be removed effectively with an increase in magnetic flux intensity. The results of electron probe microanalysis(EPMA) clearly indicated that the average intensity of the B Ka line in the α-Al phase region of Al-Si-Sn alloy is higher in the case of solidification under TMF than that of normal solidification condition, suggesting that the electromagnetic stirring can promote the B removal from the primary Si phase.展开更多
The distribution coefficient (LB) of boron between CaO?SiO2?BaO?CaF2 slag and silicon was investigated usingelectromagnetic induction melting for the purpose of improving the boron removal fraction. The dependence of ...The distribution coefficient (LB) of boron between CaO?SiO2?BaO?CaF2 slag and silicon was investigated usingelectromagnetic induction melting for the purpose of improving the boron removal fraction. The dependence of the borondistribution coefficient between slag and silicon on the fundamental parameters of CaO to SiO2 mass ratio and refining time and theadditions of BaO and CaF2 to the slag was discussed. The results show that LB can be increased by adding BaO and CaF2 toCaO?SiO2 slag. The maximum value of LB (6.94) is obtained when the CaO to SiO2 mass ratio is 1.1:1 and the contents of BaO andCaF2 are fixed at 15% and 20%, respectively. Increasing the refining time increases the LB. After the slag treatment is performedtwice, the boron content of the silicon is successfully reduced from 3.5×10?5 to 3.7×10?6, and the removal fraction of boron reaches89.4%.展开更多
基金supported by the National Natural Science Foundation of China(Nos.51471042,51501028,and 51271042)
文摘Separation of primary Si phase and removal of boron in the primary Si phase during the solidification process of the Al-30%Si-10%Sn melt under a traveling magnetic field(TMF) were investigated. The results showed that the agglomeration layer of the primary Si can be formed in the periphery of the ingot while the inner microstructures mainly consist of the eutectic α-Al+Si and β-Sn phases. The intense melt flow carries the bulk liquid with higher Si content to promote the growth of the primary Si phase which is first precipitated close to the inner wall of crucible with a relatively lower temperature, resulting in the remarkable segregation of the primary Si phase. The content of impurity B in the primary Si phase can be removed effectively with an increase in magnetic flux intensity. The results of electron probe microanalysis(EPMA) clearly indicated that the average intensity of the B Ka line in the α-Al phase region of Al-Si-Sn alloy is higher in the case of solidification under TMF than that of normal solidification condition, suggesting that the electromagnetic stirring can promote the B removal from the primary Si phase.
基金Projects(51501028,51471042,51375070)supported by the National Natural Science Foundation of ChinaProject supported by the Fundamental Research Funds of the Central Universities,China
文摘The distribution coefficient (LB) of boron between CaO?SiO2?BaO?CaF2 slag and silicon was investigated usingelectromagnetic induction melting for the purpose of improving the boron removal fraction. The dependence of the borondistribution coefficient between slag and silicon on the fundamental parameters of CaO to SiO2 mass ratio and refining time and theadditions of BaO and CaF2 to the slag was discussed. The results show that LB can be increased by adding BaO and CaF2 toCaO?SiO2 slag. The maximum value of LB (6.94) is obtained when the CaO to SiO2 mass ratio is 1.1:1 and the contents of BaO andCaF2 are fixed at 15% and 20%, respectively. Increasing the refining time increases the LB. After the slag treatment is performedtwice, the boron content of the silicon is successfully reduced from 3.5×10?5 to 3.7×10?6, and the removal fraction of boron reaches89.4%.
