(1. 江西理工大学 机电工程学院，赣州341000；
2. 江西理工大学 材料科学与工程学院，赣州341000)
摘 要: 采用自制变频控制的电磁搅拌装置制备半固态ZL203铝合金浆料，分析不同搅拌时间和搅拌频率下初生α相的形貌和尺寸，研究在连续搅拌过程中变换频率对合金熔体进行分级搅拌的影响。结果表明：分级搅拌可以有效地改善半固态合金浆料的质量；适合于半固态ZL203合金的分级电磁搅拌工艺如下：ZL203合金经670 ℃浇注后，先在40 Hz的频率下搅拌5 s，再在30 Hz的频率下搅拌10 s，并于620 ℃温度下保温5 min。经此工艺制备的半固态ZL203合金铸锭具有较好质量：其中心部区域晶粒平均等积圆直径为85.62 μm，平均形状因子为0.86；边缘区域晶粒的平均等积圆直径为84.52 μm，平均形状因子达到0.85。
关键字: ZL203铝合金；半固态；分级搅拌；Lorenz力
（1. School of Mechanical and Electrical Engineering,
Jiangxi University of Science and Technology, Ganzhou 341000, China;
2. School of Materials Science and Engineering,
Jiangxi University of Science and Technology, Ganzhou 341000, China）
Abstract:The semisolid ZL203 alloy slurry was prepared by a self-made electromagnetic stirring unit with frequency conversion. The morphology and size of primary α(Al) phase were analyzed under different stirring times and frequencies, and the effect of stepped stirring on the melt was researched by changing the frequency during continuous stirring. The results indicate that the quality of semisolid alloy slurry is effectively improved by stepped stirring, and the suitable technology of stepped stirring for semisolid ZL203 alloy is obtained as follows: ZL203 alloy poured at 670 ℃, and stirred at 40 Hz for 5 s, then at 30 Hz for 10 s, and isothermally held at 620 ℃ for 5 min, finally. The quality of semisolid ZL203 alloy ingot is relatively high, in which the average equal-area-circle grain diameter and average morphology factor of primary α phase at the central and edge position are 85.62, 84.52 μm and 0.86, 0.85, respectively.
Key words: ZL203 alloy; semisolid; stepped stirring; Lorenz force
