以2219铝合金轧制板材为研究对象,通过仿真分析、电脉冲辅助时效热处理试验、拉伸力学性能测试和透射电镜观察,系统研究了低密度电脉冲对板材时效热处理过程中电流密度分布、焦耳热效应及其时效后的力学性能与析出相微观组织的影响.结果表明:电脉冲辅助时效热处理过程中,板材峰值电流密度呈中心对称分布;80 A/cm2低密度脉冲电流作用下,板材大部分区域的峰值电流密度值在40～120A/cm2范围,温升最大不超过1℃.与常规时效工艺相比,电脉冲辅助时效热处理工艺促进了晶内强化相析出进程,同时改善了晶内析出相分布,使板材峰时效时间从15h缩短到10h,峰时效屈服强度也从283MPa提升到303MPa.综上所述,电脉冲辅助时效工艺有利于缩短铝合金板材时效热处理周期并改善峰时效力学性能.%The electric pulse assisted aging process of 2219 aluminum alloy plates is simulated and studied by ex periments.The effect of electric pulse on the current density distribution,Joule heat effect,mechanical properties and precipitates microstructure is investigated by simulation analysis,electric pulse assisted aging test,tensile test and transmission electron microscopy observation.The results show that the peak current density of the electric pulse assisted aged plate is symmetrically distributed.Under the current density of 80A/cm2,the peak current density in most areas of the sheet is between 40 and 120A/cm2.Meanwhile,the temperature rise of the plate is less than 1 ℃.Compared with the conventional aging process,the aging precipitation process is accelerated and the distribution of precipitates is homogenized after the electric pulse assisted aging process.The peak aging time was shortened from 15h to 10h,peak aging yield strength also increased from 283MPa to 303MPa.Furthermore,it indicated that the electric pulse assisted aging process can shorten the production time and improve the mechanical properties of the studied alloy.
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