工程科学学报，第41卷，第1期：96-103,2019年1月 Chinese Journal of Engineering,Vol.41,No.I:96-103,January 2019 DOI:10.13374/j.issn2095-9389.2019.01.010;http://journals.ustb.edu.cn 大直径铝锭热顶铸造中超声施振深度的细晶机制 王莹12)，李晓谦12,3)，李瑞卿2,3)区，田阳12) 1)中南大学机电工程学院，长沙4100832)高性能复杂制造国家重点实验室，长沙410083 3)中南大学轻合金研究院，长沙410083 ☒通信作者，E-mail:187430@126.com 摘要在直径为650mm的铝合金热顶半连续铸造过程中施加双源超声振动系统，研究3种超声辐射杆浸入深度对铸锭宏 观凝固组织的影响.基于铝合金铸锭凝固组织形貌的检测结果以及ANSYS等有限元软件对铸造过程中声场的仿真结果，深 入探讨了超声辐射杆在不同的施振深度下对铝合金铸锭凝固组织细化机制的影响.结果表明：随着超声辐射杆施振深度的增 加，铸锭截面组织整体进一步细化，晶粒形状由发达的枝晶变为等轴枝晶：由于超声辐射杆端面以及柱面存在几个固定位置 处振动波峰，在铝熔体中不同的超声施振深度下存在不同的超声空化范围，进而导致凝固组织的细化机制也不同. 关键词铝合金：热顶铸造：有限元法；振动波峰：超声空化：细化机制 分类号TG148:TB559 Fine grain mechanism of ultrasonic vibration depth in large diameter aluminum ingot hot-top casting WANG Ying.2),LI Xiao-qian'.23),LI Rui-qing.,TIAN Yang.2) 1)College of Mechanical and Electrical Engineering,Central South University,Changsha 410083,China 2)State Key Laboratory of High Performance Complex Manufacturing,Changsha 410083,China 3)Light Alloy Research Institute,Central South University,Changsha 410083,China Corresponding author,E-mail:Il87430@126.com ABSTRACT With the development of the aerospace industry and the need for industrialized production,the casting processes of large diameter aluminum alloy ingot have come into focus in the industry.Among them,ultrasonic-assisted casting technology is widely used.Ultrasonic-assisted casting technology has the advantages of improving solute segregation of ingot and refining solidification organ- ization.Other advantages have been widely reported.At present,most of the aluminum ingots used in the non-hot top ultrasonic casting process with very shallow liquid cavities,while the casting process does not involve the issue of ultrasonic vibration depth.With the use of a hot-top mold for ultrasound in the casting and casting process of large diameter ingot,the liquid level of aluminum melt is very high.The ultrasonic vibration depth will affect the cavitation range and finally affect the fine grain effect of the ingot.In the present study,a double source ultrasonic vibration system was applied in the process of semi-continuous casting of aluminum alloy with a diam- eter of 650 mm,and the influence of ultrasonic immersion depth on the macroscopic solidification structure of ingot was studied.Based on the test results of the solidified microstructure of aluminum alloy ingot and the simulation results of the sound field of the finite ele- ment software such as ANSYS,the mechanism of the microstructure refinement of the aluminum alloy ingot under different vibration depths was discussed at length.Study results show that,with increasing vibrational depth of the supersonic radiation rod,the whole cross section of the ingot is further refined,and grain shape changs from developed dendrites to equiaxed dendrites.Because of the end 收稿日期：2017-12-07 基金项目：国家自然科学基金资助项目(51475480,51575539,51605496，U1637601):中南大学研究生自主探索创新资助项目(1053320171530)工程科学学报,第 41 卷,第 1 期:96鄄鄄103,2019 年 1 月 Chinese Journal of Engineering, Vol. 41, No. 1: 96鄄鄄103, January 2019 DOI: 10. 13374 / j. issn2095鄄鄄9389. 2019. 01. 010; http: / / journals. ustb. edu. cn 大直径铝锭热顶铸造中超声施振深度的细晶机制 王 莹1,2) , 李晓谦1,2,3) , 李瑞卿2,3)苣 , 田 阳1,2) 1) 中南大学机电工程学院, 长沙 410083 2) 高性能复杂制造国家重点实验室, 长沙 410083 3) 中南大学轻合金研究院, 长沙 410083 苣通信作者, E鄄mail: lll87430@ 126. com 摘 要 在直径为 650 mm 的铝合金热顶半连续铸造过程中施加双源超声振动系统,研究 3 种超声辐射杆浸入深度对铸锭宏 观凝固组织的影响. 基于铝合金铸锭凝固组织形貌的检测结果以及 ANSYS 等有限元软件对铸造过程中声场的仿真结果,深 入探讨了超声辐射杆在不同的施振深度下对铝合金铸锭凝固组织细化机制的影响. 结果表明:随着超声辐射杆施振深度的增 加,铸锭截面组织整体进一步细化,晶粒形状由发达的枝晶变为等轴枝晶;由于超声辐射杆端面以及柱面存在几个固定位置 处振动波峰,在铝熔体中不同的超声施振深度下存在不同的超声空化范围,进而导致凝固组织的细化机制也不同. 关键词 铝合金; 热顶铸造; 有限元法; 振动波峰; 超声空化; 细化机制 分类号 TG148; TB559 收稿日期: 2017鄄鄄12鄄鄄07 基金项目: 国家自然科学基金资助项目(51475480,51575539,51605496,U1637601);中南大学研究生自主探索创新资助项目(1053320171530) Fine grain mechanism of ultrasonic vibration depth in large diameter aluminum ingot hot鄄top casting WANG Ying 1, 2) , LI Xiao鄄qian 1, 2,3) , LI Rui鄄qing 2, 3)苣 , TIAN Yang 1, 2) 1) College of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China 2) State Key Laboratory of High Performance Complex Manufacturing, Changsha 410083, China 3) Light Alloy Research Institute, Central South University, Changsha 410083, China 苣 Corresponding author,E鄄mail:lll87430@ 126. com ABSTRACT With the development of the aerospace industry and the need for industrialized production, the casting processes of large diameter aluminum alloy ingot have come into focus in the industry. Among them, ultrasonic鄄assisted casting technology is widely used. Ultrasonic鄄assisted casting technology has the advantages of improving solute segregation of ingot and refining solidification organ鄄 ization. Other advantages have been widely reported. At present, most of the aluminum ingots used in the non鄄hot top ultrasonic casting process with very shallow liquid cavities, while the casting process does not involve the issue of ultrasonic vibration depth. With the use of a hot鄄top mold for ultrasound in the casting and casting process of large diameter ingot, the liquid level of aluminum melt is very high. The ultrasonic vibration depth will affect the cavitation range and finally affect the fine grain effect of the ingot. In the present study, a double source ultrasonic vibration system was applied in the process of semi鄄continuous casting of aluminum alloy with a diam鄄 eter of 650 mm, and the influence of ultrasonic immersion depth on the macroscopic solidification structure of ingot was studied. Based on the test results of the solidified microstructure of aluminum alloy ingot and the simulation results of the sound field of the finite ele鄄 ment software such as ANSYS, the mechanism of the microstructure refinement of the aluminum alloy ingot under different vibration depths was discussed at length. Study results show that, with increasing vibrational depth of the supersonic radiation rod, the whole cross section of the ingot is further refined, and grain shape changs from developed dendrites to equiaxed dendrites. Because of the end