AuCu纳米薄膜中孪晶-位错相互作用的原子尺度观察

AuCu纳米薄膜中孪晶-位错相互作用的原子尺度观察

冯元元，王占鑫，马  琰，张  旭，杨成鹏^*，王立华^*，韩晓东

(1. 北京工业大学固体微结构与性能研究所，北京市先进材料微结构与性能重点实验室，北京 100124；2. 中国科学院苏州纳米技术与纳米仿生研究所，江苏 苏州 215123；3. 南方科技大学材料科学与工程系，广东 深圳 518000)

摘　要　　本文利用原位实验技术，在透射电镜中对AuCu合金纳米薄膜中的孪晶与位错相互作用行为进行了原子尺度观察。原位原子尺度实验研究发现了多种位错-孪晶相互作用行为，即偏位错交叉滑移诱导孪晶增厚行为、全位错穿越孪晶界行为，以及全位错在孪晶界分解重组诱导退孪晶行为。本实验为理解纳米合金材料中孪晶-位错反应机理提供了原位原子尺度证据，对利用缺陷相互作用提高纳米合金材料的强韧性具有一定借鉴意义。

关键词　　纳米晶薄膜；塑性变形；位错；孪晶

中图分类号：O733; TG115. 5⁺2; TG115. 21⁺5. 3    

文献标识码：A Doi:10.3969/j.issn.1000-6281.2025.06.002

Atomic-scale observation of twin-dislocation interactions in AuCu nanofilms

FENG Yuanyuan¹, WANG Zhanxin¹, MA Yan¹, ZHANG Xu¹, YANG Chengpeng^1，2*, WANG Lihua^1*, HAN Xiaodong^1，3

(1. Beijing Key Lab of Microstructure and Property of Advanced Material, Institute of Microstructure and Properties of Advanced Materials, Beijing University of Technology, Beijing 100124; 2. Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou Jiangsu 215123；Department of Materials Science and Engineering, Nanfang University of Science and Technology, Shenzhen Guangdong 518000，China)

Abstract　　In this study, atomic-scale observations of twin-dislocation interactions in AuCu alloy nanofilms were conducted using in situ transmission electron microscopy. The in-situ experiments revealed various interaction behaviors dislocations and twins, including biased dislocation cross-slip induced twin thickening, transmission of full dislocations across twin boundaries, and dissociation and recombination of full dislocations leading to detwinning. These observations provide direct atomic-scale evidence for understanding the mechanisms of twin-dislocation reactions in nano-alloyed materials, offering valuable insights for optimzing defect interactions to improve the strength and toughness of nano-alloyed materials.

Keywords　　nanocrystalline thin films; plastic deformation; dislocations; twins

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