摘要
通过直流电沉积技术制备具有高密度纳米孪晶结构的Ni,并对该材料中存在的五次孪晶结构进行了深入系统的电子显微分析.获得了纳米孪晶Ni中五次孪晶结构的HRTEM图像和SAED花样;研究了单个晶粒内部五次孪晶的结构特性、分布规律.结果表明,五次孪晶是由5个{111}晶体旋转组成,五次旋转孪晶产生的7.35°本征间隙至少由五次孪晶中的2个孪晶界分担;而且分担间隙的孪晶界呈现宽化现象,并且分解为新的孪晶,导致五次孪晶晶粒在整体形状上不具有五次对称性,呈现出一定的不规则形状.TEM截面形貌分析表明,电沉积纳米孪晶Ni呈现{110}面平行样品表面织构,晶粒为柱状晶分布,柱状生长方向为[110].通过综合结构表征,给出了五次孪晶在三维空间的结构模型.
The nanocrystalline Ni thin films with high density nano-scale growth twins were synthesized by direct electrodeposition technology. The five-fold twinning structure in electrodeposited nano-twin Ni was systematically investigated by TEM. The remarkable diffraction pattern and HRTEM images obtained from the cross-section observation demonstrate directly that the electrodeposited nano-twin Ni has five-fold twinning structure with five { 111 } twinned subcrystals and systematically analyzed the 7.35° intrinsic structural gap. In this work, the 7.35° gap was at least inset in two twin boundaries of the five-fold twin, the twin boundaries which share the 7.35° gap always broaden and was decomposed into other twins, so that, the grain present a irregular shape, cross-sectional TEM micrograph revealed that the electrodeposited nano-twin Ni had columnar grain structure with a strong { 110} texture. By means of comprehensive structure characterization, a new space structural model of the five-fold twin was proposed.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2014年第3期305-312,共8页
Acta Metallurgica Sinica
基金
国家自然科学基金项目11374027和51001003
北京市教委重点基金项目KZ201010005002资助~~
关键词
电沉积
纳米孪晶Ni
显微结构
透射电镜(TEM)
五次孪晶
electrodeposition, nanao-twin Ni, microstructure, transmission electron microscopy （TEM）,five-fold twin
