脉冲电流辅助作用下纳米晶Ni箔低应变速率变形行为及成形工艺  

Deformation behavior and forming process of nanocrystalline Ni foil with low strain rate assisted by pulse current

作　　者：杜金洋 李超[1] 陈子帅 邹庆[1] DU Jin-yang;LI Chao;CHEN Zi-shuai;ZOU Qing(School of Material Science and Chemical Engineering,Harbin University of Science and Technology,Harbin 150040,China)

机构地区：[1]哈尔滨理工大学材料科学与化学工程学院,黑龙江哈尔滨150040

出　　处：《塑性工程学报》2023年第6期239-248,共10页Journal of Plasticity Engineering

基　　金：国家自然科学基金资助项目(51975167);黑龙江省普通高校基本科研业务专项资金资助项目(2019-KYYWF-0220)。

摘　　要：针对纳米晶金属箔材塑性成形性能低和成形困难的问题,以纳米晶Ni箔为研究对象,研究了脉冲电流辅助作用下其单向拉伸、低应变速率条件下的变形行为。采用SEM和TEM观察了拉伸试样的断口形貌及微观组织变化。结果表明,随着脉冲峰值电流密度的提高,纳米晶Ni箔的成形性能明显改善,在温度为350℃、应变速率为7×10^(-4)s^(-1),峰值电流密度为500 A·mm^(-2)时,添加了3%ZrO2的Ni箔的伸长率达到12.3%。显微组织及织构分析表明,脉冲电流的施加改变了材料的断裂类型,并在一定程度上影响了晶粒内部及晶界处的位错运动,进一步增强了纳米晶粒以箔材厚度方向为轴的转动性,从而提升了材料的变形性能。此外,根据材料的变形特点,改进或提出了几种脉冲电流辅助纳米晶金属箔材成形方法。To solve the problems of low plastic forming performance and difficult forming of nanocrystalline metal foil,the deformation behaviors of nanocrystalline Ni foil were studied,which occur at the condition of uniaxial tension and low strain rate assisted by pulse cur⁃rent.The fracture morphology and microstructure of tensile specimens were observed by SEM and TEM.The results show that the forming properties of nanocrystalline Ni foil are improved with the increase of peak pulse current density.The elongation of Ni foil added 3%ZrO2 reaches 12.3%at 350℃,strain rate of 7×10^(-4)s^(-1)and peak current density of 500 A·mm^(-2).The microstructure and texture analysis show that the application of pulse current changes the fracture type of the material,and the dislocation movement in the grains and at the grain boundaries is influenced to some extent.Furthermore,the rotation of the nanocrystalline grains with the direction of the thickness of the foil is enhanced,so the deformation performance of the meterial is improved.In addition,several methods for pulse current assis⁃ted nanocrystalline metal foil forming were improved or proposed according to the deformation characteristics of the material.

关 键 词：纳米晶箔材 电致塑性效应 变形行为 微观组织 

分 类 号：TG306[金属学及工艺—金属压力加工]