(1. 江西理工大學(xué) 機電工程學(xué)院，贛州 341000；
2. 江西理工大學(xué) 材料科學(xué)與工程學(xué)院，贛州 341000)
摘 要: 采用數(shù)值模擬，建立磁場二維有限元模型和流場三維有限元模型，研究電磁攪拌參數(shù)對磁感應(yīng)強度、電磁力、半固態(tài)鋁合金熔體最大流速的影響，以及對初生相的影響。結(jié)果表明：由于集膚效應(yīng)，熔體中電磁力由內(nèi)向外逐漸增強，磁感應(yīng)強度隨電磁頻率的增大呈現(xiàn)出“中心小，邊緣大”的特征，且在結(jié)晶器徑向的0.80R~0.85R處達到最大值；在電磁攪拌頻率為25 Hz、電流為4 A、攪拌時間為12 s時，熔體流速較其他參數(shù)最大；半固態(tài)A356鋁合金在650 ℃澆鑄后恒溫電磁攪拌，在電磁攪拌參數(shù)為30 Hz、4 A時攪拌12 s后，590 ℃保溫10 min得到的初生相形貌最佳，此時平均等積圓直徑為80.6 μm，形狀因子為0.78。
關(guān)鍵字: 半固態(tài)；A356鋁合金；電磁場；流場；數(shù)值模擬；電磁攪拌
（1. School of Mechanical and Electronic Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China;
2. School of Material Science and Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China）
Abstract:A two-dimensional finite element model of magnetic field and a three-dimensional finite element model of flow field were established by using numerical simulation to study the effects of electromagnetic stirring parameters on magnetic induction strength, electromagnetic force, and the maximum flow rate of semi-solid aluminum alloy melt, as well as on the primary phase. The results show that the electromagnetic force in the melt gradually increased from inside to outside due to the skin accumulation effect, and the magnetic induction intensity show the characteristics of “small center and large edge” with the increase of electromagnetic frequency, and reach the maximum value at 0.80R-0.85R of the radial direction of the crystallizer. When the electromagnetic stirring frequency is 25 Hz, the current is 4 A, and the stirred time is 12 s, the melt flow rate is the largest compared with other parameters. The morphologies of primary phases of semi-solid A356 aluminum alloy cast at 650 ℃ are the best after electromagnetic stirring at 590 ℃ for 10 min at stirring parameters of 590 ℃, 30 Hz, 4 A and 12 s. Finally, the microstructure of semi-solid A356 alloy with the average grain equal-area circle diameter of 80.6 μm and the shape factor of 0.78 is obtained.
Key words: semi-solid; A356 aluminum alloy; electromagnetic field; flow field; numerical simulation; Electromagnetic stirring
