Enhanced tensile ductility of tungsten microwires via high-density dislocations and reduced grain boundaries  

作　　者：Chaoqun Dang Weitong Lin Fanling Meng Hongti Zhang Sufeng Fan Xiaocui Li Ke Cao Haokun Yang Wenzhao Zhou Zhengjie Fan Ji-jung Kai Yang Lu 

机构地区：[1]Department of Mechanical Engineering,City University of Hong Kong,Hong Kong,China [2]Department of Materials Science and Engineering,Southern University of Science and Technology,Shenzhen,China [3]School of Physical Science and Technology,ShanghaiTech University,Shanghai,China [4]Nano-Manufacturing Laboratory(NML),Shenzhen Research Institute,City University of Hong Kong,Shenzhen,China [5]State Key Laboratory for Manufacturing Systems Engineering,Xi'an Jiaotong University,Xi'an,China [6]Centre for Advanced Nuclear Safety and Sustainable Development,City University of Hong Kong,Hong Kong,China

出　　处：《Journal of Materials Science & Technology》2021年第36期193-202,共10页材料科学技术（英文版）

基　　金：supported by the Hong Kong Research Grant Council(RGC)under projects City U11207416;National Natural Science Foundation of China(NSFC)under grant 11922215;City University of Hong Kong under grant 7005234 and 9667194。

摘　　要：Despite being strong with many outstanding physical properties,tungsten is inherently brittle at room temperature,restricting its structural and functional applications at small scales.Here,a facile strategy has been adopted,to introduce high-density dislocations while reducing grain boundaries,through electron backscatter diffraction(EBSD)-guided microfabrication of cold-drawn bulk tungsten wires.The designed tungsten microwire attains an ultralarge uniform tensile elongation of~10.6%,while retains a high yield strength of~2.4 GPa.in situ TEM tensile testing reveals that the large uniform elongation of tungsten microwires originates from the motion of pre-existing high-density dislocations,while the subsequent ductile fracture is attributed to crack-tip plasticity and the inhibition of grain boundary cracking.This work demonstrates the application potential of tungsten microcomponents with superior ductility and workability for micro/nanoscale mechanical,electronic,and energy systems.

关 键 词：TUNGSTEN DISLOCATION Grain boundary DUCTILITY In situ TEM Nanomechanics 

分 类 号：TG146.411[一般工业技术—材料科学与工程]