超声振动对近共晶Al-Si活塞合金凝固组织的影响  

Effect of Ultrasonic Vibration on Solidification Microstructure in Near-Eutectic Al-Si Piston Alloy

作　　者：董雄博 郭永春[1] 李建平[1] 夏峰[1] 马志军[1] 杨伟[1] 王建利[1] 胥涛 梁民宪[1] Dong Xiongbo;Guo Yongchun;Li Jianping;Xia Feng;Ma Zhijun;Yang Wei;Wang Jianli;Xu Tao;Liang Minxian(School of Materials Science and Chemical Engineering,Xi'an Technological University,Xi'an 710021,China;Xi'an Comboo New Materials Technology Co.,Ltd,Xi'an 710117,China)

机构地区：[1]西安工业大学材料与化工学院,陕西西安710021 [2]西安康博新材料科技有限公司,陕西西安710117

出　　处：《稀有金属材料与工程》2022年第1期11-17,共7页Rare Metal Materials and Engineering

基　　金：Shaanxi Provincial Scientific and Technological Research Project (S2018-YF-ZDLGY-0070);Shaanxi Creative Talents Promotion PlanTechnological Innovation Team (2017KCT-05)。

摘　　要：研究了超声振动对Al-11.5Si-4Cu-2Ni-1Mg-0.45Fe合金凝固组织的影响。结果表明,经超声振动的合金中,初生硅形貌由长条状转变为多边形状,并得到了显著细化。其中空化效应产生的大过冷度引起的异质形核和生长时间缩短是初生硅细化的主要原因。随着超声功率的增加,初生硅由长条状转变为短棒状,α-Al;Fe Si相由块状转变为半圆形态。共晶硅和金属间化合物形态的演变和细化主要是由空化效应引起的固体破碎、均匀的溶质分布、均匀的温度场及共晶生长时间的缩短造成的。The effect of ultrasonic vibration(USV) on solidification microstructure of Al-11.5 Si-4 Cu-2 Ni-1 Mg-0.45 Fe(wt%) piston alloy was investigated. Results show that the significant refinement and morphology transformation from strip into compact polygon can be observed for the primary Si in the alloys produced by USV. The enhanced heterogeneous nucleation and shortened growth time caused by the large undercooling which is triggered by cavitation are responsible for the refinement of primary Si. The morphology of eutectic Si gradually develops from long plate into a short plate structure with increasing the ultrasonic power. Meanwhile, the morphology of α-Al5 Fe Si phases changes from coarsening block shape to half circle. The morphology evolution and refinement of eutectic Si as well as intermetallic particles are mainly due to the fragmentation of solid crystals, homogeneous solute distribution field and temperature field, and shortened eutectic growth time caused by cavitation.

关 键 词：AL-SI合金 超声振动 组织 形核 

分 类 号：TG663[金属学及工艺—金属切削加工及机床] TG146.21[一般工业技术—材料科学与工程]