Enhanced tensile ductility and strength of electrodeposited ultrafine-grained nickel with a desired bimodal microstructure

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:701

Article

Zhang, Qian^1,2  Liu, Ying^1,2  Liu, Yongsheng^1,2  Ren, Yanhong^1,2  Wu, Yanxia¹  Gao, Zhipeng³  Wu, Xiaolei⁴  Han, Peide^1,2 

[1] Taiyuan Univ Technol, Coll Mat Sci & Engn, Taiyuan 030024, Peoples R China

[2] Taiyuan Univ Technol, Key Lab Interface Sci & Engn Adv Mat, Taiyuan 030024, Peoples R China

[3] Taiyuan Univ Technol, Coll Mech, Inst Appl Mech & Biomed Engn, Taiyuan 030024, Peoples R China

[4] Chinese Acad Sci, Inst Mech, State Key Lab Nonlinear Mech, Beijing 100190, Peoples R China

关键词: Electrodeposition;    Nickel;    Bimodal microstructure;    Twins;    Spatial distribution;    Mechanical property;   

DOI  :  10.1016/j.msea.2017.06.063

来源: Elsevier

【 摘 要 】

This work aims to use surfactant-assisted direct current electrodeposition technique to prepare four types of bimodal nickel, under different current densities. Bimodal Ni is obtained with different grain size and spatial distribution of CG and UFG areas showing a big disparity in mechanical properties. As a result of small population of coarse-grained surrounded by quite a lot of ultrafine-grained forming a unique shell-and-core bimodal structure, bimodal one present the best comprehensive mechanical properties with an ultrahigh tensile strength (similar to 847 MPa) and a considerable plastic strain (similar to 16.7%). Deformation initial, bimodal structures display more positive strain hardening to meaningful strains than unimodal structure of UFG and CG. Particularly bimodal one work-hardening rate is the highest thanks to its structure (UFG occupy 76.7% in total number fraction) and the distribution of growth twins. Growth twins in this article are referred to Sigma 3(111) coherent twins playing an important role in improving high strength, enhancing uniform plastic deformation ability.

【 授权许可】

Free