可控电磁能(CEME)时效处理下Al-Zn-Mg-Cu合金的析出及强化机理研究  

Precipitation and Strengthening Mechanism of Al-Zn-Mg-Cu Alloy UnderControllable Electromagnetic Energy(CEME)Aging Treatment

作　　者：白庆伟 麻永林 邢淑清 于文霞 陈重毅 BAI Qingwei;MA Yonglin;XING Shuqing;YU Wenxia;CHEN Zhongyi(School of Material and Metallurgy(School of Rare Earth),Inner Mongolia University of Science&Technology,Baotou 014010,China;Key Laboratory of Comprehensive Utilization of Polymetallic Resources of Bayan Obo Mine,Inner Mongolia Autonomous Region,Baotou 014010,China)

机构地区：[1]内蒙古科技大学材料与冶金学院(稀土学院),包头014010 [2]内蒙古自治区白云鄂博矿多金属资源综合利用重点实验室,包头014010

出　　处：《材料导报》2021年第20期20143-20148,20160,共7页Materials Reports

基　　金：内蒙古自治区自然科学基金(2020BS05021,2018MS05008);内蒙古科技大学创新基金(2019QDL-B16);内蒙古自治区重大基础研究开放课题(0406091701);内蒙古自治区科技计划项目(2021GG0095);国家留学基金委员会的留学资助(201708150077)。

摘　　要：文中提出了可控电磁能(CEME)铝合金辅助时效处理技术,研究了脉冲电磁场产生的可控电磁能对Al-Zn-Mg-Cu合金析出相密度、尺寸分布及力学性能的影响并分析了组织强化机制。引入磁-热扩散模型和量子力学探讨外加脉冲磁能作用下Al-Zn-Mg-Cu合金的扩散析出机理。结果表明,施加脉冲电磁场有利于增加析出质点数量,而延长时效可促进析出相长大,经脉冲电磁场时效1 h后的析出相分布密度为1.124μm^(-2),约为传统时效12 h的3倍,其抗拉强度分别为506 MPa和542 MPa;随着析出相尺寸的增大,强化机理由共格应变场强化机制(OS)过渡至Orowan绕过强化模型(CS),理论临界析出颗粒尺寸为20 nm。动力学分析认为,外加磁能对扩散激活能的G tot作用较小,提高原子振动频率v 0是增加析出质点数量的主要原因。Pulsed electromagnetic fields could induce controlled electromagnetic energy(CEME).Auxiliary aging treatment of Al-Zn-Mg-Cu alloy was performed by pulsed electromagnetic field.The effects of pulsed electromagnetic field on the precipitation density,size distribution and mechanical properties were investigated,and the mechanism of microstructure strengthening was analyzed.The magnetic-thermal diffusion model and quantum mechanics were introduced to explore the evolution of precipitation phase under pulsed magnetic energy.The results showed that the number of precipitated particles increases under the pulsed electromagnetic field,while prolonged aging time promotes the growth of the precipitated phase.The density of the precipitated phase is 1.124μm^(-2) after pulsed electromagnetic field aging for 1 h,which is about three times the traditional aging 12 h.The strengths of aged Al-Zn-Mg-Cu alloy are 506 MPa and 542 MPa,respectively.The strengthening mechanism of precipitation changes from coherent strain field strengthening mechanism(CS)transitions to the Orowan by pass strengthening model(OS)with the increase of the precipitate size,and the theoretical critical precipitate size is 20 nm.The kinetic analysis indicates that the electromagnetic energy almost has no effect on the diffusion activation energy,and increasing the atomic vibration frequency is the main reason for increasing the number of precipitated particles.

关 键 词：析出强化 外加磁能 磁-热扩散模型 Larmor频率 

分 类 号：TF821[冶金工程—有色金属冶金]