A356铝合金半固态浆料的双向弱电磁搅拌与等温处理工艺的研究  

Two-Way Slightly Electron Magnetic Stirring and Isothermal Treatment of A356 Aluminum Alloy Semi-solid Slurry

作　　者：刘政[1] 陈涛[1] 陈志平 刘小梅[1] Liu Zheng;Chen Tao;Chen Zhiping;Liu Xiaomei(Jiangxi University of Science and Technology,Ganzhou 341000,China)

机构地区：[1]江西理工大学

出　　处：《稀有金属材料与工程》2019年第5期1664-1670,共7页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51144009,51361012);江西省自然科学基金(20142bab206012);江西省教育厅科技项目(GJJ14407)

摘　　要：结合弱电磁搅拌和熔体等温保温技术,提出了一种复合浆料制备新工艺:双向弱电磁搅拌+等温保温处理。研究了铝熔体双向弱电磁搅拌后等温温度580~610℃、等温保温时间3~15 min对凝固组织形貌演化规律的影响。结果表明,在不同的等温保温参数作用下,随着温度升高、时间延长,初生相尺寸逐渐细化球化,但等温温度和等温时间存在阈值。超过阈值,初生相反而粗化。经过对比初生相形貌可知,在等温温度600℃、等温时间7 min条件下初生相的尺寸细化和球化程度达到最佳,平均等积圆直径为29.4μm,形状因子0.86。因此,该温度和时间是半固态A356铝合金在复合工艺条件下,匹配合理的熔体等温处理工艺参数。通过该新型复合工艺可制备出品质合格的半固态铝合金浆料。A new technology combining slightly electromagnetic stirring and melt isothermal holding technology was formed: Two-way slightly electromagnetic stirring and isothermal holding. The effects of the isothermal holding temperature from 580 to 610℃ and the isothermal holding time from 3 to 15 min on the evolution of solidification microstructure were researched. The results indicate that under different isothermal heat treatment parameters, as the temperature increases and time extends, the size of the primary grains is gradually refined and spheroidized. However, the threshold value of the isothermal holding temperature and time could be found, so the grains become coarse above the threshold value. By comparing the microstructure of the grain, it is found that the proper parameters are the isothermal holding temperature of 600℃ and the isothermal holding time of 7 min, when the average equal-area circle diameter and average shape factor of the primary phase are 29.4 μm and 0.86,respectively. Therefore, the temperature and time are the reasonably-matched melt isothermal holding process parameters for the semisolid A356 aluminum alloy in the composite process. The qualified semisolid aluminum alloy slurry could be prepared by the new composite process.

关 键 词：半固态 A356铝合金 双向弱电磁搅拌 等温保温 凝固组织 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TG244[金属学及工艺—金属材料]