工程科学学报，第41卷，第9期：1135-1141,2019年9月 Chinese Journal of Engineering,Vol.41,No.9:1135-1141,September 2019 DOI:10.13374/j.issn2095-9389.2019.09.004;http://journals.ustb.edu.cn 超声对熔盐电解法制备A1-7Si-Sc合金组织的影响 郭志超，刘轩，薛济来四，张鹏举 北京科技大学治金与生态工程学院，北京100083 区通信作者，E-mail:jx@usth.edu.cm 摘要A-Sⅰ系合金在现代工业、交通等领域广泛应用，合金元素钪可进一步改善其加工和使用性能.采用超声协同熔盐电 解法制备A1-7S-Sc三元合金，研究探索超声作用对合金组织及强化相分布的影响.发现超声协同熔盐电解制得合金中Sc含 量提高，团簇共晶硅组织和A1Si,SC,相显著细化，共晶硅团簇尺寸由约500降低至200μm,减小约60%，细化后A1Si,SC,相分布 均匀.超声协同电解法可显著优化A-7S-Sc合金组织，有助于控制改善现行工艺中合金元素偏聚、组织不均匀现象. 关键词A-Si合金；共晶硅；AISi,SC2;超声波：熔盐电解法 分类号TS912·.3 Effects of ultrasound on the microstructure of Al-7Si-Sc alloy prepared via molten salt electrolysis GUO Zhi-chao,LIU Xuan,XUE Ji-lai,ZHANG Peng-ju School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing,Beijing 100083,China Corresponding author,E-mail:jx@ustb.edu.cn ABSTRACT Al-Si alloys are widely used in modern industries.transportation,and other engineering applications.Processability and mechanical properties of Al-based alloys can be improved via the addition of scandium.Sc added to Al metal for fabricating Sc-con- taining Al alloys using molten salt electrolysis has been recently considered as promising technology.However,alloying elements,such as Sc and Si are often unevenly distributed in such Al-based alloys.In this study,Al-7Si-Sc terary alloy was prepared via molten salt electrolysis aided with ultrasound to investigate the effects of ultrasound on the microstructure and distribution of the strengthening phase.Electrolysis was performed on molten salts of Na AlF-19%KF-29%AlF,-2%CaF,at a temperature of 800 C and current den- sity of 1A.cm2,in which Sc2(99.99%purity)and Al-7Si alloy served as the raw material and cathodic metal,respectively.Ultra- sound (20 kHz,200 W)was introduced into the cathode metal from the cell bottom.Sc contents in the as-prepared alloy samples were determined using inductively coupled plasma atomic emission spectrometry (ICP-AES).Microstructures of the alloy samples were characterized using optical microscope and scanning electron microscope coupled with an energy dispersive X-ray analyzer.Results re- veal that ultrasound can increase Sc content in the ternary alloy prepared via molten salt electrolysis and refine the eutectic silicon clus- ters and the ternary AlSi,Sc,phase.Compared with the alloys made without ultrasound aid,the silicon cluster size decreases from ap- proximately 500 to 200 um (60%)and the refined ternary phase of AlSiSe uniformly distributes in the metal matrix.Results also indicate that ultrasound can considerably optimize the microstructure of Al-7Si-Sc alloy prepared via molten salt electrolysis.This process can prevent problems such as the segregation of alloying elements and uneven microstructures observed when using the tradition- al alloy-making process. KEY WORDS Al-Si alloy;eutectic silicon;AlSi,Se2;ultrasound;molten salt electrolysis 收稿日期：2019-01-29 基金项目：国家自然科学基金资助项目(51434005,51704020,51874035)：北京市自然科学基金资助项目(2184110)工程科学学报,第 41 卷,第 9 期:1135鄄鄄1141,2019 年 9 月 Chinese Journal of Engineering, Vol. 41, No. 9: 1135鄄鄄1141, September 2019 DOI: 10. 13374 / j. issn2095鄄鄄9389. 2019. 09. 004; http: / / journals. ustb. edu. cn 超声对熔盐电解法制备 Al鄄鄄7Si鄄鄄 Sc 合金组织的影响 郭志超, 刘 轩, 薛济来苣 , 张鹏举 北京科技大学冶金与生态工程学院, 北京 100083 苣通信作者, E鄄mail: jx@ ustb. edu. cn 摘 要 Al鄄鄄 Si 系合金在现代工业、交通等领域广泛应用,合金元素钪可进一步改善其加工和使用性能. 采用超声协同熔盐电 解法制备 Al鄄鄄7S鄄鄄 Sc 三元合金,研究探索超声作用对合金组织及强化相分布的影响. 发现超声协同熔盐电解制得合金中 Sc 含 量提高,团簇共晶硅组织和 AlSi 2 Sc2相显著细化,共晶硅团簇尺寸由约500 降低至200滋m,减小约60% ,细化后 AlSi 2 Sc2相分布 均匀. 超声协同电解法可显著优化 Al鄄鄄7Si鄄鄄 Sc 合金组织,有助于控制改善现行工艺中合金元素偏聚、组织不均匀现象. 关键词 Al鄄鄄 Si 合金; 共晶硅; AlSi 2 Sc2 ; 超声波; 熔盐电解法 分类号 TS912 + 郾 3 收稿日期: 2019鄄鄄01鄄鄄29 基金项目: 国家自然科学基金资助项目(51434005,51704020,51874035);北京市自然科学基金资助项目(2184110) Effects of ultrasound on the microstructure of Al鄄鄄7Si鄄鄄Sc alloy prepared via molten salt electrolysis GUO Zhi鄄chao, LIU Xuan, XUE Ji鄄lai 苣 , ZHANG Peng鄄ju School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China 苣Corresponding author, E鄄mail: jx@ ustb. edu. cn ABSTRACT Al鄄鄄 Si alloys are widely used in modern industries, transportation, and other engineering applications. Processability and mechanical properties of Al鄄based alloys can be improved via the addition of scandium. Sc added to Al metal for fabricating Sc鄄con鄄 taining Al alloys using molten salt electrolysis has been recently considered as promising technology. However, alloying elements, such as Sc and Si are often unevenly distributed in such Al鄄based alloys. In this study, Al鄄鄄7Si鄄鄄Sc ternary alloy was prepared via molten salt electrolysis aided with ultrasound to investigate the effects of ultrasound on the microstructure and distribution of the strengthening phase. Electrolysis was performed on molten salts of Na3AlF6 鄄鄄19% KF鄄鄄29% AlF3 鄄鄄2% CaF2 at a temperature of 800 益 and current den鄄 sity of 1A·cm 2 , in which Sc2O3 (99郾 99% purity) and Al鄄鄄7Si alloy served as the raw material and cathodic metal, respectively. Ultra鄄 sound (20 kHz, 200 W) was introduced into the cathode metal from the cell bottom. Sc contents in the as鄄prepared alloy samples were determined using inductively coupled plasma atomic emission spectrometry ( ICP鄄鄄 AES). Microstructures of the alloy samples were characterized using optical microscope and scanning electron microscope coupled with an energy dispersive X鄄ray analyzer. Results re鄄 veal that ultrasound can increase Sc content in the ternary alloy prepared via molten salt electrolysis and refine the eutectic silicon clus鄄 ters and the ternary AlSi 2 Sc2 phase. Compared with the alloys made without ultrasound aid, the silicon cluster size decreases from ap鄄 proximately 500 to 200 滋m ( ~ 60% ) and the refined ternary phase of AlSi 2 Sc2 uniformly distributes in the metal matrix. Results also indicate that ultrasound can considerably optimize the microstructure of Al鄄鄄 7Si鄄鄄 Sc alloy prepared via molten salt electrolysis. This process can prevent problems such as the segregation of alloying elements and uneven microstructures observed when using the tradition鄄 al alloy鄄making process. KEY WORDS Al鄄鄄 Si alloy; eutectic silicon; AlSi 2 Sc2 ; ultrasound; molten salt electrolysis